root/third_party/libevent/http.c

DEFINITIONS

1. fake_getnameinfo
2. fake_getaddrinfo
3. fake_freeaddrinfo
4. strsep
5. html_replace
6. evhttp_htmlescape
7. evhttp_method
8. evhttp_add_event
9. evhttp_write_buffer
10. evhttp_connected
11. evhttp_make_header_request
12. evhttp_is_connection_close
13. evhttp_is_connection_keepalive
14. evhttp_maybe_add_date_header
15. evhttp_maybe_add_content_length_header
16. evhttp_make_header_response
17. evhttp_make_header
18. evhttp_hostportfile
19. evhttp_connection_incoming_fail
20. evhttp_connection_fail
21. evhttp_write
22. evhttp_connection_done
23. evhttp_handle_chunked_read
24. evhttp_read_trailer
25. evhttp_read_body
26. evhttp_read
27. evhttp_write_connectioncb
28. evhttp_connection_free
29. evhttp_connection_set_local_address
30. evhttp_connection_set_local_port
31. evhttp_request_dispatch
32. evhttp_connection_reset
33. evhttp_detect_close_cb
34. evhttp_connection_start_detectclose
35. evhttp_connection_stop_detectclose
36. evhttp_connection_retry
37. evhttp_connectioncb
38. evhttp_valid_response_code
39. evhttp_parse_response_line
40. evhttp_parse_request_line
41. evhttp_find_header
42. evhttp_clear_headers
43. evhttp_remove_header
44. evhttp_header_is_valid_value
45. evhttp_add_header
46. evhttp_add_header_internal
47. evhttp_parse_firstline
48. evhttp_append_to_last_header
49. evhttp_parse_headers
50. evhttp_get_body_length
51. evhttp_get_body
52. evhttp_read_firstline
53. evhttp_read_header
54. evhttp_connection_new
55. evhttp_connection_set_base
56. evhttp_connection_set_timeout
57. evhttp_connection_set_retries
58. evhttp_connection_set_closecb
59. evhttp_connection_get_peer
60. evhttp_connection_connect
61. evhttp_make_request
62. evhttp_start_read
63. evhttp_send_done
64. evhttp_send_error
65. evhttp_send
66. evhttp_send_reply
67. evhttp_send_reply_start
68. evhttp_send_reply_chunk
69. evhttp_send_reply_end
70. evhttp_response_code
71. evhttp_send_page
72. evhttp_encode_uri
73. evhttp_decode_uri_internal
74. evhttp_decode_uri
75. evhttp_parse_query
76. evhttp_dispatch_callback
77. evhttp_handle_request
78. accept_socket
79. evhttp_bind_socket
80. evhttp_accept_socket
81. evhttp_new_object
82. evhttp_new
83. evhttp_start
84. evhttp_free
85. evhttp_set_timeout
86. evhttp_set_cb
87. evhttp_del_cb
88. evhttp_set_gencb
89. evhttp_request_new
90. evhttp_request_free
91. evhttp_request_set_chunked_cb
92. evhttp_request_uri
93. evhttp_get_request_connection
94. evhttp_associate_new_request_with_connection
95. evhttp_get_request
96. addr_from_name
97. name_from_addr
98. bind_socket_ai
99. make_addrinfo
100. bind_socket
101. socket_connect

/*
 * Copyright (c) 2002-2006 Niels Provos <provos@citi.umich.edu>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif

#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_SYS_IOCCOM_H
#include <sys/ioccom.h>
#endif

#ifndef WIN32
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/wait.h>
#endif

#include <sys/queue.h>

#ifndef WIN32
#include <netinet/in.h>
#include <netdb.h>
#endif

#ifdef WIN32
#include <winsock2.h>
#endif

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef WIN32
#include <syslog.h>
#endif
#include <signal.h>
#include <time.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

#undef timeout_pending
#undef timeout_initialized

#include "strlcpy-internal.h"
#include "event.h"
#include "evhttp.h"
#include "evutil.h"
#include "log.h"
#include "http-internal.h"

#ifdef WIN32
#define strcasecmp _stricmp
#define strncasecmp _strnicmp
#define strdup _strdup
#endif

#ifndef HAVE_GETNAMEINFO
#define NI_MAXSERV 32
#define NI_MAXHOST 1025

#define NI_NUMERICHOST 1
#define NI_NUMERICSERV 2

static int
fake_getnameinfo(const struct sockaddr *sa, size_t salen, char *host, 
        size_t hostlen, char *serv, size_t servlen, int flags)
{
        struct sockaddr_in *sin = (struct sockaddr_in *)sa;
        
        if (serv != NULL) {
                                char tmpserv[16];
                                evutil_snprintf(tmpserv, sizeof(tmpserv),
                                        "%d", ntohs(sin->sin_port));
                if (strlcpy(serv, tmpserv, servlen) >= servlen)
                        return (-1);
        }

        if (host != NULL) {
                if (flags & NI_NUMERICHOST) {
                        if (strlcpy(host, inet_ntoa(sin->sin_addr),
                            hostlen) >= hostlen)
                                return (-1);
                        else
                                return (0);
                } else {
                                                struct hostent *hp;
                        hp = gethostbyaddr((char *)&sin->sin_addr, 
                            sizeof(struct in_addr), AF_INET);
                        if (hp == NULL)
                                return (-2);
                        
                        if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
                                return (-1);
                        else
                                return (0);
                }
        }
        return (0);
}

#endif

#ifndef HAVE_GETADDRINFO
struct addrinfo {
        int ai_family;
        int ai_socktype;
        int ai_protocol;
        size_t ai_addrlen;
        struct sockaddr *ai_addr;
        struct addrinfo *ai_next;
};
static int
fake_getaddrinfo(const char *hostname, struct addrinfo *ai)
{
        struct hostent *he = NULL;
        struct sockaddr_in *sa;
        if (hostname) {
                he = gethostbyname(hostname);
                if (!he)
                        return (-1);
        }
        ai->ai_family = he ? he->h_addrtype : AF_INET;
        ai->ai_socktype = SOCK_STREAM;
        ai->ai_protocol = 0;
        ai->ai_addrlen = sizeof(struct sockaddr_in);
        if (NULL == (ai->ai_addr = malloc(ai->ai_addrlen)))
                return (-1);
        sa = (struct sockaddr_in*)ai->ai_addr;
        memset(sa, 0, ai->ai_addrlen);
        if (he) {
                sa->sin_family = he->h_addrtype;
                memcpy(&sa->sin_addr, he->h_addr_list[0], he->h_length);
        } else {
                sa->sin_family = AF_INET;
                sa->sin_addr.s_addr = INADDR_ANY;
        }
        ai->ai_next = NULL;
        return (0);
}
static void
fake_freeaddrinfo(struct addrinfo *ai)
{
        free(ai->ai_addr);
}
#endif

#ifndef MIN
#define MIN(a,b) (((a)<(b))?(a):(b))
#endif

/* wrapper for setting the base from the http server */
#define EVHTTP_BASE_SET(x, y) do { \
        if ((x)->base != NULL) event_base_set((x)->base, y);    \
} while (0) 

extern int debug;

static int socket_connect(int fd, const char *address, unsigned short port);
static int bind_socket_ai(struct addrinfo *, int reuse);
static int bind_socket(const char *, u_short, int reuse);
static void name_from_addr(struct sockaddr *, socklen_t, char **, char **);
static int evhttp_associate_new_request_with_connection(
        struct evhttp_connection *evcon);
static void evhttp_connection_start_detectclose(
        struct evhttp_connection *evcon);
static void evhttp_connection_stop_detectclose(
        struct evhttp_connection *evcon);
static void evhttp_request_dispatch(struct evhttp_connection* evcon);
static void evhttp_read_firstline(struct evhttp_connection *evcon,
                                  struct evhttp_request *req);
static void evhttp_read_header(struct evhttp_connection *evcon,
    struct evhttp_request *req);
static int evhttp_add_header_internal(struct evkeyvalq *headers,
    const char *key, const char *value);
static int evhttp_decode_uri_internal(const char *uri, size_t length,
    char *ret, int always_decode_plus);

void evhttp_read(int, short, void *);
void evhttp_write(int, short, void *);

#ifndef HAVE_STRSEP
/* strsep replacement for platforms that lack it.  Only works if
 * del is one character long. */
static char *
strsep(char **s, const char *del)
{
        char *d, *tok;
        assert(strlen(del) == 1);
        if (!s || !*s)
                return NULL;
        tok = *s;
        d = strstr(tok, del);
        if (d) {
                *d = '\0';
                *s = d + 1;
        } else
                *s = NULL;
        return tok;
}
#endif

static const char *
html_replace(char ch, char *buf)
{
        switch (ch) {
        case '<':
                return "&lt;";
        case '>':
                return "&gt;";
        case '"':
                return "&quot;";
        case '\'':
                return "&#039;";
        case '&':
                return "&amp;";
        default:
                break;
        }

        /* Echo the character back */
        buf[0] = ch;
        buf[1] = '\0';
        
        return buf;
}

/*
 * Replaces <, >, ", ' and & with &lt;, &gt;, &quot;,
 * &#039; and &amp; correspondingly.
 *
 * The returned string needs to be freed by the caller.
 */

char *
evhttp_htmlescape(const char *html)
{
        int i, new_size = 0, old_size = strlen(html);
        char *escaped_html, *p;
        char scratch_space[2];
        
        for (i = 0; i < old_size; ++i)
          new_size += strlen(html_replace(html[i], scratch_space));

        p = escaped_html = malloc(new_size + 1);
        if (escaped_html == NULL)
                event_err(1, "%s: malloc(%d)", __func__, new_size + 1);
        for (i = 0; i < old_size; ++i) {
                const char *replaced = html_replace(html[i], scratch_space);
                /* this is length checked */
                strcpy(p, replaced);
                p += strlen(replaced);
        }

        *p = '\0';

        return (escaped_html);
}

static const char *
evhttp_method(enum evhttp_cmd_type type)
{
        const char *method;

        switch (type) {
        case EVHTTP_REQ_GET:
                method = "GET";
                break;
        case EVHTTP_REQ_POST:
                method = "POST";
                break;
        case EVHTTP_REQ_HEAD:
                method = "HEAD";
                break;
        default:
                method = NULL;
                break;
        }

        return (method);
}

static void
evhttp_add_event(struct event *ev, int timeout, int default_timeout)
{
        if (timeout != 0) {
                struct timeval tv;
                
                evutil_timerclear(&tv);
                tv.tv_sec = timeout != -1 ? timeout : default_timeout;
                event_add(ev, &tv);
        } else {
                event_add(ev, NULL);
        }
}

void
evhttp_write_buffer(struct evhttp_connection *evcon,
    void (*cb)(struct evhttp_connection *, void *), void *arg)
{
        event_debug(("%s: preparing to write buffer\n", __func__));

        /* Set call back */
        evcon->cb = cb;
        evcon->cb_arg = arg;

        /* check if the event is already pending */
        if (event_pending(&evcon->ev, EV_WRITE|EV_TIMEOUT, NULL))
                event_del(&evcon->ev);

        event_set(&evcon->ev, evcon->fd, EV_WRITE, evhttp_write, evcon);
        EVHTTP_BASE_SET(evcon, &evcon->ev);
        evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_WRITE_TIMEOUT);
}

static int
evhttp_connected(struct evhttp_connection *evcon)
{
        switch (evcon->state) {
        case EVCON_DISCONNECTED:
        case EVCON_CONNECTING:
                return (0);
        case EVCON_IDLE:
        case EVCON_READING_FIRSTLINE:
        case EVCON_READING_HEADERS:
        case EVCON_READING_BODY:
        case EVCON_READING_TRAILER:
        case EVCON_WRITING:
        default:
                return (1);
        }
}

/*
 * Create the headers needed for an HTTP request
 */
static void
evhttp_make_header_request(struct evhttp_connection *evcon,
    struct evhttp_request *req)
{
        const char *method;
        
        evhttp_remove_header(req->output_headers, "Proxy-Connection");

        /* Generate request line */
        method = evhttp_method(req->type);
        evbuffer_add_printf(evcon->output_buffer, "%s %s HTTP/%d.%d\r\n",
            method, req->uri, req->major, req->minor);

        /* Add the content length on a post request if missing */
        if (req->type == EVHTTP_REQ_POST &&
            evhttp_find_header(req->output_headers, "Content-Length") == NULL){
                char size[12];
                evutil_snprintf(size, sizeof(size), "%ld",
                    (long)EVBUFFER_LENGTH(req->output_buffer));
                evhttp_add_header(req->output_headers, "Content-Length", size);
        }
}

static int
evhttp_is_connection_close(int flags, struct evkeyvalq* headers)
{
        if (flags & EVHTTP_PROXY_REQUEST) {
                /* proxy connection */
                const char *connection = evhttp_find_header(headers, "Proxy-Connection");
                return (connection == NULL || strcasecmp(connection, "keep-alive") != 0);
        } else {
                const char *connection = evhttp_find_header(headers, "Connection");
                return (connection != NULL && strcasecmp(connection, "close") == 0);
        }
}

static int
evhttp_is_connection_keepalive(struct evkeyvalq* headers)
{
        const char *connection = evhttp_find_header(headers, "Connection");
        return (connection != NULL 
            && strncasecmp(connection, "keep-alive", 10) == 0);
}

static void
evhttp_maybe_add_date_header(struct evkeyvalq *headers)
{
        if (evhttp_find_header(headers, "Date") == NULL) {
                char date[50];
#ifndef WIN32
                struct tm cur;
#endif
                struct tm *cur_p;
                time_t t = time(NULL);
#ifdef WIN32
                cur_p = gmtime(&t);
#else
                gmtime_r(&t, &cur);
                cur_p = &cur;
#endif
                if (strftime(date, sizeof(date),
                        "%a, %d %b %Y %H:%M:%S GMT", cur_p) != 0) {
                        evhttp_add_header(headers, "Date", date);
                }
        }
}

static void
evhttp_maybe_add_content_length_header(struct evkeyvalq *headers,
    long content_length)
{
        if (evhttp_find_header(headers, "Transfer-Encoding") == NULL &&
            evhttp_find_header(headers, "Content-Length") == NULL) {
                char len[12];
                evutil_snprintf(len, sizeof(len), "%ld", content_length);
                evhttp_add_header(headers, "Content-Length", len);
        }
}

/*
 * Create the headers needed for an HTTP reply
 */

static void
evhttp_make_header_response(struct evhttp_connection *evcon,
    struct evhttp_request *req)
{
        int is_keepalive = evhttp_is_connection_keepalive(req->input_headers);
        evbuffer_add_printf(evcon->output_buffer, "HTTP/%d.%d %d %s\r\n",
            req->major, req->minor, req->response_code,
            req->response_code_line);

        if (req->major == 1) {
                if (req->minor == 1)
                        evhttp_maybe_add_date_header(req->output_headers);

                /*
                 * if the protocol is 1.0; and the connection was keep-alive
                 * we need to add a keep-alive header, too.
                 */
                if (req->minor == 0 && is_keepalive)
                        evhttp_add_header(req->output_headers,
                            "Connection", "keep-alive");

                if (req->minor == 1 || is_keepalive) {
                        /* 
                         * we need to add the content length if the
                         * user did not give it, this is required for
                         * persistent connections to work.
                         */
                        evhttp_maybe_add_content_length_header(
                                req->output_headers,
                                (long)EVBUFFER_LENGTH(req->output_buffer));
                }
        }

        /* Potentially add headers for unidentified content. */
        if (EVBUFFER_LENGTH(req->output_buffer)) {
                if (evhttp_find_header(req->output_headers,
                        "Content-Type") == NULL) {
                        evhttp_add_header(req->output_headers,
                            "Content-Type", "text/html; charset=ISO-8859-1");
                }
        }

        /* if the request asked for a close, we send a close, too */
        if (evhttp_is_connection_close(req->flags, req->input_headers)) {
                evhttp_remove_header(req->output_headers, "Connection");
                if (!(req->flags & EVHTTP_PROXY_REQUEST))
                    evhttp_add_header(req->output_headers, "Connection", "close");
                evhttp_remove_header(req->output_headers, "Proxy-Connection");
        }
}

void
evhttp_make_header(struct evhttp_connection *evcon, struct evhttp_request *req)
{
        struct evkeyval *header;

        /*
         * Depending if this is a HTTP request or response, we might need to
         * add some new headers or remove existing headers.
         */
        if (req->kind == EVHTTP_REQUEST) {
                evhttp_make_header_request(evcon, req);
        } else {
                evhttp_make_header_response(evcon, req);
        }

        TAILQ_FOREACH(header, req->output_headers, next) {
                evbuffer_add_printf(evcon->output_buffer, "%s: %s\r\n",
                    header->key, header->value);
        }
        evbuffer_add(evcon->output_buffer, "\r\n", 2);

        if (EVBUFFER_LENGTH(req->output_buffer) > 0) {
                /*
                 * For a request, we add the POST data, for a reply, this
                 * is the regular data.
                 */
                evbuffer_add_buffer(evcon->output_buffer, req->output_buffer);
        }
}

/* Separated host, port and file from URI */

int
evhttp_hostportfile(char *url, char **phost, u_short *pport, char **pfile)
{
        /* XXX not threadsafe. */
        static char host[1024];
        static char file[1024];
        char *p;
        const char *p2;
        int len;
        u_short port;

        len = strlen(HTTP_PREFIX);
        if (strncasecmp(url, HTTP_PREFIX, len))
                return (-1);

        url += len;

        /* We might overrun */
        if (strlcpy(host, url, sizeof (host)) >= sizeof(host))
                return (-1);

        p = strchr(host, '/');
        if (p != NULL) {
                *p = '\0';
                p2 = p + 1;
        } else
                p2 = NULL;

        if (pfile != NULL) {
                /* Generate request file */
                if (p2 == NULL)
                        p2 = "";
                evutil_snprintf(file, sizeof(file), "/%s", p2);
        }

        p = strchr(host, ':');
        if (p != NULL) {
                *p = '\0';
                port = atoi(p + 1);

                if (port == 0)
                        return (-1);
        } else
                port = HTTP_DEFAULTPORT;

        if (phost != NULL)
                *phost = host;
        if (pport != NULL)
                *pport = port;
        if (pfile != NULL)
                *pfile = file;

        return (0);
}

static int
evhttp_connection_incoming_fail(struct evhttp_request *req,
    enum evhttp_connection_error error)
{
        switch (error) {
        case EVCON_HTTP_TIMEOUT:
        case EVCON_HTTP_EOF:
                /* 
                 * these are cases in which we probably should just
                 * close the connection and not send a reply.  this
                 * case may happen when a browser keeps a persistent
                 * connection open and we timeout on the read.
                 */
                return (-1);
        case EVCON_HTTP_INVALID_HEADER:
        default:        /* xxx: probably should just error on default */
                /* the callback looks at the uri to determine errors */
                if (req->uri) {
                        free(req->uri);
                        req->uri = NULL;
                }

                /* 
                 * the callback needs to send a reply, once the reply has
                 * been send, the connection should get freed.
                 */
                (*req->cb)(req, req->cb_arg);
        }
        
        return (0);
}

void
evhttp_connection_fail(struct evhttp_connection *evcon,
    enum evhttp_connection_error error)
{
        struct evhttp_request* req = TAILQ_FIRST(&evcon->requests);
        void (*cb)(struct evhttp_request *, void *);
        void *cb_arg;
        assert(req != NULL);
        
        if (evcon->flags & EVHTTP_CON_INCOMING) {
                /* 
                 * for incoming requests, there are two different
                 * failure cases.  it's either a network level error
                 * or an http layer error. for problems on the network
                 * layer like timeouts we just drop the connections.
                 * For HTTP problems, we might have to send back a
                 * reply before the connection can be freed.
                 */
                if (evhttp_connection_incoming_fail(req, error) == -1)
                        evhttp_connection_free(evcon);
                return;
        }

        /* save the callback for later; the cb might free our object */
        cb = req->cb;
        cb_arg = req->cb_arg;

        TAILQ_REMOVE(&evcon->requests, req, next);
        evhttp_request_free(req);

        /* xxx: maybe we should fail all requests??? */

        /* reset the connection */
        evhttp_connection_reset(evcon);
        
        /* We are trying the next request that was queued on us */
        if (TAILQ_FIRST(&evcon->requests) != NULL)
                evhttp_connection_connect(evcon);

        /* inform the user */
        if (cb != NULL)
                (*cb)(NULL, cb_arg);
}

void
evhttp_write(int fd, short what, void *arg)
{
        struct evhttp_connection *evcon = arg;
        int n;

        if (what == EV_TIMEOUT) {
                evhttp_connection_fail(evcon, EVCON_HTTP_TIMEOUT);
                return;
        }

        n = evbuffer_write(evcon->output_buffer, fd);
        if (n == -1) {
                event_debug(("%s: evbuffer_write", __func__));
                evhttp_connection_fail(evcon, EVCON_HTTP_EOF);
                return;
        }

        if (n == 0) {
                event_debug(("%s: write nothing", __func__));
                evhttp_connection_fail(evcon, EVCON_HTTP_EOF);
                return;
        }

        if (EVBUFFER_LENGTH(evcon->output_buffer) != 0) {
                evhttp_add_event(&evcon->ev, 
                    evcon->timeout, HTTP_WRITE_TIMEOUT);
                return;
        }

        /* Activate our call back */
        if (evcon->cb != NULL)
                (*evcon->cb)(evcon, evcon->cb_arg);
}

/**
 * Advance the connection state.
 * - If this is an outgoing connection, we've just processed the response;
 *   idle or close the connection.
 * - If this is an incoming connection, we've just processed the request;
 *   respond.
 */
static void
evhttp_connection_done(struct evhttp_connection *evcon)
{
        struct evhttp_request *req = TAILQ_FIRST(&evcon->requests);
        int con_outgoing = evcon->flags & EVHTTP_CON_OUTGOING;

        if (con_outgoing) {
                /* idle or close the connection */
                int need_close;
                TAILQ_REMOVE(&evcon->requests, req, next);
                req->evcon = NULL;

                evcon->state = EVCON_IDLE;

                need_close = 
                    evhttp_is_connection_close(req->flags, req->input_headers)||
                    evhttp_is_connection_close(req->flags, req->output_headers);

                /* check if we got asked to close the connection */
                if (need_close)
                        evhttp_connection_reset(evcon);

                if (TAILQ_FIRST(&evcon->requests) != NULL) {
                        /*
                         * We have more requests; reset the connection
                         * and deal with the next request.
                         */
                        if (!evhttp_connected(evcon))
                                evhttp_connection_connect(evcon);
                        else
                                evhttp_request_dispatch(evcon);
                } else if (!need_close) {
                        /*
                         * The connection is going to be persistent, but we
                         * need to detect if the other side closes it.
                         */
                        evhttp_connection_start_detectclose(evcon);
                }
        } else {
                /*
                 * incoming connection - we need to leave the request on the
                 * connection so that we can reply to it.
                 */
                evcon->state = EVCON_WRITING;
        }

        /* notify the user of the request */
        (*req->cb)(req, req->cb_arg);

        /* if this was an outgoing request, we own and it's done. so free it */
        if (con_outgoing) {
                evhttp_request_free(req);
        }
}

/*
 * Handles reading from a chunked request.
 *   return ALL_DATA_READ:
 *     all data has been read
 *   return MORE_DATA_EXPECTED:
 *     more data is expected
 *   return DATA_CORRUPTED:
 *     data is corrupted
 *   return REQUEST_CANCLED:
 *     request was canceled by the user calling evhttp_cancel_request
 */

static enum message_read_status
evhttp_handle_chunked_read(struct evhttp_request *req, struct evbuffer *buf)
{
        int len;

        while ((len = EVBUFFER_LENGTH(buf)) > 0) {
                if (req->ntoread < 0) {
                        /* Read chunk size */
                        ev_int64_t ntoread;
                        char *p = evbuffer_readline(buf);
                        char *endp;
                        int error;
                        if (p == NULL)
                                break;
                        /* the last chunk is on a new line? */
                        if (strlen(p) == 0) {
                                free(p);
                                continue;
                        }
                        ntoread = evutil_strtoll(p, &endp, 16);
                        error = (*p == '\0' ||
                            (*endp != '\0' && *endp != ' ') ||
                            ntoread < 0);
                        free(p);
                        if (error) {
                                /* could not get chunk size */
                                return (DATA_CORRUPTED);
                        }
                        req->ntoread = ntoread;
                        if (req->ntoread == 0) {
                                /* Last chunk */
                                return (ALL_DATA_READ);
                        }
                        continue;
                }

                /* don't have enough to complete a chunk; wait for more */
                if (len < req->ntoread)
                        return (MORE_DATA_EXPECTED);

                /* Completed chunk */
                evbuffer_add(req->input_buffer,
                    EVBUFFER_DATA(buf), (size_t)req->ntoread);
                evbuffer_drain(buf, (size_t)req->ntoread);
                req->ntoread = -1;
                if (req->chunk_cb != NULL) {
                        (*req->chunk_cb)(req, req->cb_arg);
                        evbuffer_drain(req->input_buffer,
                            EVBUFFER_LENGTH(req->input_buffer));
                }
        }

        return (MORE_DATA_EXPECTED);
}

static void
evhttp_read_trailer(struct evhttp_connection *evcon, struct evhttp_request *req)
{
        struct evbuffer *buf = evcon->input_buffer;

        switch (evhttp_parse_headers(req, buf)) {
        case DATA_CORRUPTED:
                evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER);
                break;
        case ALL_DATA_READ:
                event_del(&evcon->ev);
                evhttp_connection_done(evcon);
                break;
        case MORE_DATA_EXPECTED:
        default:
                evhttp_add_event(&evcon->ev, evcon->timeout,
                    HTTP_READ_TIMEOUT);
                break;
        }
}

static void
evhttp_read_body(struct evhttp_connection *evcon, struct evhttp_request *req)
{
        struct evbuffer *buf = evcon->input_buffer;
        
        if (req->chunked) {
                switch (evhttp_handle_chunked_read(req, buf)) {
                case ALL_DATA_READ:
                        /* finished last chunk */
                        evcon->state = EVCON_READING_TRAILER;
                        evhttp_read_trailer(evcon, req);
                        return;
                case DATA_CORRUPTED:
                        /* corrupted data */
                        evhttp_connection_fail(evcon,
                            EVCON_HTTP_INVALID_HEADER);
                        return;
                case REQUEST_CANCELED:
                        /* request canceled */
                        evhttp_request_free(req);
                        return;
                case MORE_DATA_EXPECTED:
                default:
                        break;
                }
        } else if (req->ntoread < 0) {
                /* Read until connection close. */
                evbuffer_add_buffer(req->input_buffer, buf);
        } else if (EVBUFFER_LENGTH(buf) >= req->ntoread) {
                /* Completed content length */
                evbuffer_add(req->input_buffer, EVBUFFER_DATA(buf),
                    (size_t)req->ntoread);
                evbuffer_drain(buf, (size_t)req->ntoread);
                req->ntoread = 0;
                evhttp_connection_done(evcon);
                return;
        }
        /* Read more! */
        event_set(&evcon->ev, evcon->fd, EV_READ, evhttp_read, evcon);
        EVHTTP_BASE_SET(evcon, &evcon->ev);
        evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT);
}

/*
 * Reads data into a buffer structure until no more data
 * can be read on the file descriptor or we have read all
 * the data that we wanted to read.
 * Execute callback when done.
 */

void
evhttp_read(int fd, short what, void *arg)
{
        struct evhttp_connection *evcon = arg;
        struct evhttp_request *req = TAILQ_FIRST(&evcon->requests);
        struct evbuffer *buf = evcon->input_buffer;
        int n, len;

        if (what == EV_TIMEOUT) {
                evhttp_connection_fail(evcon, EVCON_HTTP_TIMEOUT);
                return;
        }
        n = evbuffer_read(buf, fd, -1);
        len = EVBUFFER_LENGTH(buf);
        event_debug(("%s: got %d on %d\n", __func__, n, fd));
        
        if (n == -1) {
                if (errno != EINTR && errno != EAGAIN) {
                        event_debug(("%s: evbuffer_read", __func__));
                        evhttp_connection_fail(evcon, EVCON_HTTP_EOF);
                } else {
                        evhttp_add_event(&evcon->ev, evcon->timeout,
                            HTTP_READ_TIMEOUT);        
                }
                return;
        } else if (n == 0) {
                /* Connection closed */
                evhttp_connection_done(evcon);
                return;
        }

        switch (evcon->state) {
        case EVCON_READING_FIRSTLINE:
                evhttp_read_firstline(evcon, req);
                break;
        case EVCON_READING_HEADERS:
                evhttp_read_header(evcon, req);
                break;
        case EVCON_READING_BODY:
                evhttp_read_body(evcon, req);
                break;
        case EVCON_READING_TRAILER:
                evhttp_read_trailer(evcon, req);
                break;
        case EVCON_DISCONNECTED:
        case EVCON_CONNECTING:
        case EVCON_IDLE:
        case EVCON_WRITING:
        default:
                event_errx(1, "%s: illegal connection state %d",
                           __func__, evcon->state);
        }
}

static void
evhttp_write_connectioncb(struct evhttp_connection *evcon, void *arg)
{
        /* This is after writing the request to the server */
        struct evhttp_request *req = TAILQ_FIRST(&evcon->requests);
        assert(req != NULL);

        assert(evcon->state == EVCON_WRITING);

        /* We are done writing our header and are now expecting the response */
        req->kind = EVHTTP_RESPONSE;

        evhttp_start_read(evcon);
}

/*
 * Clean up a connection object
 */

void
evhttp_connection_free(struct evhttp_connection *evcon)
{
        struct evhttp_request *req;

        /* notify interested parties that this connection is going down */
        if (evcon->fd != -1) {
                if (evhttp_connected(evcon) && evcon->closecb != NULL)
                        (*evcon->closecb)(evcon, evcon->closecb_arg);
        }

        /* remove all requests that might be queued on this connection */
        while ((req = TAILQ_FIRST(&evcon->requests)) != NULL) {
                TAILQ_REMOVE(&evcon->requests, req, next);
                evhttp_request_free(req);
        }

        if (evcon->http_server != NULL) {
                struct evhttp *http = evcon->http_server;
                TAILQ_REMOVE(&http->connections, evcon, next);
        }

        if (event_initialized(&evcon->close_ev))
                event_del(&evcon->close_ev);

        if (event_initialized(&evcon->ev))
                event_del(&evcon->ev);
        
        if (evcon->fd != -1)
                EVUTIL_CLOSESOCKET(evcon->fd);

        if (evcon->bind_address != NULL)
                free(evcon->bind_address);

        if (evcon->address != NULL)
                free(evcon->address);

        if (evcon->input_buffer != NULL)
                evbuffer_free(evcon->input_buffer);

        if (evcon->output_buffer != NULL)
                evbuffer_free(evcon->output_buffer);

        free(evcon);
}

void
evhttp_connection_set_local_address(struct evhttp_connection *evcon,
    const char *address)
{
        assert(evcon->state == EVCON_DISCONNECTED);
        if (evcon->bind_address)
                free(evcon->bind_address);
        if ((evcon->bind_address = strdup(address)) == NULL)
                event_err(1, "%s: strdup", __func__);
}

void
evhttp_connection_set_local_port(struct evhttp_connection *evcon,
    unsigned short port)
{
        assert(evcon->state == EVCON_DISCONNECTED);
        evcon->bind_port = port;
}

static void
evhttp_request_dispatch(struct evhttp_connection* evcon)
{
        struct evhttp_request *req = TAILQ_FIRST(&evcon->requests);
        
        /* this should not usually happy but it's possible */
        if (req == NULL)
                return;

        /* delete possible close detection events */
        evhttp_connection_stop_detectclose(evcon);
        
        /* we assume that the connection is connected already */
        assert(evcon->state == EVCON_IDLE);

        evcon->state = EVCON_WRITING;

        /* Create the header from the store arguments */
        evhttp_make_header(evcon, req);

        evhttp_write_buffer(evcon, evhttp_write_connectioncb, NULL);
}

/* Reset our connection state */
void
evhttp_connection_reset(struct evhttp_connection *evcon)
{
        if (event_initialized(&evcon->ev))
                event_del(&evcon->ev);

        if (evcon->fd != -1) {
                /* inform interested parties about connection close */
                if (evhttp_connected(evcon) && evcon->closecb != NULL)
                        (*evcon->closecb)(evcon, evcon->closecb_arg);

                EVUTIL_CLOSESOCKET(evcon->fd);
                evcon->fd = -1;
        }
        evcon->state = EVCON_DISCONNECTED;

        evbuffer_drain(evcon->input_buffer,
            EVBUFFER_LENGTH(evcon->input_buffer));
        evbuffer_drain(evcon->output_buffer,
            EVBUFFER_LENGTH(evcon->output_buffer));
}

static void
evhttp_detect_close_cb(int fd, short what, void *arg)
{
        struct evhttp_connection *evcon = arg;
        evhttp_connection_reset(evcon);
}

static void
evhttp_connection_start_detectclose(struct evhttp_connection *evcon)
{
        evcon->flags |= EVHTTP_CON_CLOSEDETECT;

        if (event_initialized(&evcon->close_ev))
                event_del(&evcon->close_ev);
        event_set(&evcon->close_ev, evcon->fd, EV_READ,
            evhttp_detect_close_cb, evcon);
        EVHTTP_BASE_SET(evcon, &evcon->close_ev);
        event_add(&evcon->close_ev, NULL);
}

static void
evhttp_connection_stop_detectclose(struct evhttp_connection *evcon)
{
        evcon->flags &= ~EVHTTP_CON_CLOSEDETECT;
        event_del(&evcon->close_ev);
}

static void
evhttp_connection_retry(int fd, short what, void *arg)
{
        struct evhttp_connection *evcon = arg;

        evcon->state = EVCON_DISCONNECTED;
        evhttp_connection_connect(evcon);
}

/*
 * Call back for asynchronous connection attempt.
 */

static void
evhttp_connectioncb(int fd, short what, void *arg)
{
        struct evhttp_connection *evcon = arg;
        int error;
        socklen_t errsz = sizeof(error);
                
        if (what == EV_TIMEOUT) {
                event_debug(("%s: connection timeout for \"%s:%d\" on %d",
                        __func__, evcon->address, evcon->port, evcon->fd));
                goto cleanup;
        }

        /* Check if the connection completed */
        if (getsockopt(evcon->fd, SOL_SOCKET, SO_ERROR, (void*)&error,
                       &errsz) == -1) {
                event_debug(("%s: getsockopt for \"%s:%d\" on %d",
                        __func__, evcon->address, evcon->port, evcon->fd));
                goto cleanup;
        }

        if (error) {
                event_debug(("%s: connect failed for \"%s:%d\" on %d: %s",
                    __func__, evcon->address, evcon->port, evcon->fd,
                        strerror(error)));
                goto cleanup;
        }

        /* We are connected to the server now */
        event_debug(("%s: connected to \"%s:%d\" on %d\n",
                        __func__, evcon->address, evcon->port, evcon->fd));

        /* Reset the retry count as we were successful in connecting */
        evcon->retry_cnt = 0;
        evcon->state = EVCON_IDLE;

        /* try to start requests that have queued up on this connection */
        evhttp_request_dispatch(evcon);
        return;

 cleanup:
        if (evcon->retry_max < 0 || evcon->retry_cnt < evcon->retry_max) {
                evtimer_set(&evcon->ev, evhttp_connection_retry, evcon);
                EVHTTP_BASE_SET(evcon, &evcon->ev);
                evhttp_add_event(&evcon->ev, MIN(3600, 2 << evcon->retry_cnt),
                    HTTP_CONNECT_TIMEOUT);
                evcon->retry_cnt++;
                return;
        }
        evhttp_connection_reset(evcon);

        /* for now, we just signal all requests by executing their callbacks */
        while (TAILQ_FIRST(&evcon->requests) != NULL) {
                struct evhttp_request *request = TAILQ_FIRST(&evcon->requests);
                TAILQ_REMOVE(&evcon->requests, request, next);
                request->evcon = NULL;

                /* we might want to set an error here */
                request->cb(request, request->cb_arg);
                evhttp_request_free(request);
        }
}

/*
 * Check if we got a valid response code.
 */

static int
evhttp_valid_response_code(int code)
{
        if (code == 0)
                return (0);

        return (1);
}

/* Parses the status line of a web server */

static int
evhttp_parse_response_line(struct evhttp_request *req, char *line)
{
        char *protocol;
        char *number;
        char *readable;

        protocol = strsep(&line, " ");
        if (line == NULL)
                return (-1);
        number = strsep(&line, " ");
        if (line == NULL)
                return (-1);
        readable = line;

        if (strcmp(protocol, "HTTP/1.0") == 0) {
                req->major = 1;
                req->minor = 0;
        } else if (strcmp(protocol, "HTTP/1.1") == 0) {
                req->major = 1;
                req->minor = 1;
        } else {
                event_debug(("%s: bad protocol \"%s\"",
                        __func__, protocol));
                return (-1);
        }

        req->response_code = atoi(number);
        if (!evhttp_valid_response_code(req->response_code)) {
                event_debug(("%s: bad response code \"%s\"",
                        __func__, number));
                return (-1);
        }

        if ((req->response_code_line = strdup(readable)) == NULL)
                event_err(1, "%s: strdup", __func__);

        return (0);
}

/* Parse the first line of a HTTP request */

static int
evhttp_parse_request_line(struct evhttp_request *req, char *line)
{
        char *method;
        char *uri;
        char *version;

        /* Parse the request line */
        method = strsep(&line, " ");
        if (line == NULL)
                return (-1);
        uri = strsep(&line, " ");
        if (line == NULL)
                return (-1);
        version = strsep(&line, " ");
        if (line != NULL)
                return (-1);

        /* First line */
        if (strcmp(method, "GET") == 0) {
                req->type = EVHTTP_REQ_GET;
        } else if (strcmp(method, "POST") == 0) {
                req->type = EVHTTP_REQ_POST;
        } else if (strcmp(method, "HEAD") == 0) {
                req->type = EVHTTP_REQ_HEAD;
        } else {
                event_debug(("%s: bad method %s on request %p from %s",
                        __func__, method, req, req->remote_host));
                return (-1);
        }

        if (strcmp(version, "HTTP/1.0") == 0) {
                req->major = 1;
                req->minor = 0;
        } else if (strcmp(version, "HTTP/1.1") == 0) {
                req->major = 1;
                req->minor = 1;
        } else {
                event_debug(("%s: bad version %s on request %p from %s",
                        __func__, version, req, req->remote_host));
                return (-1);
        }

        if ((req->uri = strdup(uri)) == NULL) {
                event_debug(("%s: evhttp_decode_uri", __func__));
                return (-1);
        }

        /* determine if it's a proxy request */
        if (strlen(req->uri) > 0 && req->uri[0] != '/')
                req->flags |= EVHTTP_PROXY_REQUEST;

        return (0);
}

const char *
evhttp_find_header(const struct evkeyvalq *headers, const char *key)
{
        struct evkeyval *header;

        TAILQ_FOREACH(header, headers, next) {
                if (strcasecmp(header->key, key) == 0)
                        return (header->value);
        }

        return (NULL);
}

void
evhttp_clear_headers(struct evkeyvalq *headers)
{
        struct evkeyval *header;

        for (header = TAILQ_FIRST(headers);
            header != NULL;
            header = TAILQ_FIRST(headers)) {
                TAILQ_REMOVE(headers, header, next);
                free(header->key);
                free(header->value);
                free(header);
        }
}

/*
 * Returns 0,  if the header was successfully removed.
 * Returns -1, if the header could not be found.
 */

int
evhttp_remove_header(struct evkeyvalq *headers, const char *key)
{
        struct evkeyval *header;

        TAILQ_FOREACH(header, headers, next) {
                if (strcasecmp(header->key, key) == 0)
                        break;
        }

        if (header == NULL)
                return (-1);

        /* Free and remove the header that we found */
        TAILQ_REMOVE(headers, header, next);
        free(header->key);
        free(header->value);
        free(header);

        return (0);
}

static int
evhttp_header_is_valid_value(const char *value)
{
        const char *p = value;

        while ((p = strpbrk(p, "\r\n")) != NULL) {
                /* we really expect only one new line */
                p += strspn(p, "\r\n");
                /* we expect a space or tab for continuation */
                if (*p != ' ' && *p != '\t')
                        return (0);
        }
        return (1);
}

int
evhttp_add_header(struct evkeyvalq *headers,
    const char *key, const char *value)
{
        event_debug(("%s: key: %s val: %s\n", __func__, key, value));

        if (strchr(key, '\r') != NULL || strchr(key, '\n') != NULL) {
                /* drop illegal headers */
                event_debug(("%s: dropping illegal header key\n", __func__));
                return (-1);
        }
        
        if (!evhttp_header_is_valid_value(value)) {
                event_debug(("%s: dropping illegal header value\n", __func__));
                return (-1);
        }

        return (evhttp_add_header_internal(headers, key, value));
}

static int
evhttp_add_header_internal(struct evkeyvalq *headers,
    const char *key, const char *value)
{
        struct evkeyval *header = calloc(1, sizeof(struct evkeyval));
        if (header == NULL) {
                event_warn("%s: calloc", __func__);
                return (-1);
        }
        if ((header->key = strdup(key)) == NULL) {
                free(header);
                event_warn("%s: strdup", __func__);
                return (-1);
        }
        if ((header->value = strdup(value)) == NULL) {
                free(header->key);
                free(header);
                event_warn("%s: strdup", __func__);
                return (-1);
        }

        TAILQ_INSERT_TAIL(headers, header, next);

        return (0);
}

/*
 * Parses header lines from a request or a response into the specified
 * request object given an event buffer.
 *
 * Returns
 *   DATA_CORRUPTED      on error
 *   MORE_DATA_EXPECTED  when we need to read more headers
 *   ALL_DATA_READ       when all headers have been read.
 */

enum message_read_status
evhttp_parse_firstline(struct evhttp_request *req, struct evbuffer *buffer)
{
        char *line;
        enum message_read_status status = ALL_DATA_READ;

        line = evbuffer_readline(buffer);
        if (line == NULL)
                return (MORE_DATA_EXPECTED);

        switch (req->kind) {
        case EVHTTP_REQUEST:
                if (evhttp_parse_request_line(req, line) == -1)
                        status = DATA_CORRUPTED;
                break;
        case EVHTTP_RESPONSE:
                if (evhttp_parse_response_line(req, line) == -1)
                        status = DATA_CORRUPTED;
                break;
        default:
                status = DATA_CORRUPTED;
        }

        free(line);
        return (status);
}

static int
evhttp_append_to_last_header(struct evkeyvalq *headers, const char *line)
{
        struct evkeyval *header = TAILQ_LAST(headers, evkeyvalq);
        char *newval;
        size_t old_len, line_len;

        if (header == NULL)
                return (-1);

        old_len = strlen(header->value);
        line_len = strlen(line);

        newval = realloc(header->value, old_len + line_len + 1);
        if (newval == NULL)
                return (-1);

        memcpy(newval + old_len, line, line_len + 1);
        header->value = newval;

        return (0);
}

enum message_read_status
evhttp_parse_headers(struct evhttp_request *req, struct evbuffer* buffer)
{
        char *line;
        enum message_read_status status = MORE_DATA_EXPECTED;

        struct evkeyvalq* headers = req->input_headers;
        while ((line = evbuffer_readline(buffer))
               != NULL) {
                char *skey, *svalue;

                if (*line == '\0') { /* Last header - Done */
                        status = ALL_DATA_READ;
                        free(line);
                        break;
                }

                /* Check if this is a continuation line */
                if (*line == ' ' || *line == '\t') {
                        if (evhttp_append_to_last_header(headers, line) == -1)
                                goto error;
                        free(line);
                        continue;
                }

                /* Processing of header lines */
                svalue = line;
                skey = strsep(&svalue, ":");
                if (svalue == NULL)
                        goto error;

                svalue += strspn(svalue, " ");

                if (evhttp_add_header(headers, skey, svalue) == -1)
                        goto error;

                free(line);
        }

        return (status);

 error:
        free(line);
        return (DATA_CORRUPTED);
}

static int
evhttp_get_body_length(struct evhttp_request *req)
{
        struct evkeyvalq *headers = req->input_headers;
        const char *content_length;
        const char *connection;

        content_length = evhttp_find_header(headers, "Content-Length");
        connection = evhttp_find_header(headers, "Connection");
                
        if (content_length == NULL && connection == NULL)
                req->ntoread = -1;
        else if (content_length == NULL &&
            strcasecmp(connection, "Close") != 0) {
                /* Bad combination, we don't know when it will end */
                event_warnx("%s: we got no content length, but the "
                    "server wants to keep the connection open: %s.",
                    __func__, connection);
                return (-1);
        } else if (content_length == NULL) {
                req->ntoread = -1;
        } else {
                char *endp;
                ev_int64_t ntoread = evutil_strtoll(content_length, &endp, 10);
                if (*content_length == '\0' || *endp != '\0' || ntoread < 0) {
                        event_debug(("%s: illegal content length: %s",
                                __func__, content_length));
                        return (-1);
                }
                req->ntoread = ntoread;
        }
                
        event_debug(("%s: bytes to read: %lld (in buffer %ld)\n",
                __func__, req->ntoread,
                EVBUFFER_LENGTH(req->evcon->input_buffer)));

        return (0);
}

static void
evhttp_get_body(struct evhttp_connection *evcon, struct evhttp_request *req)
{
        const char *xfer_enc;
        
        /* If this is a request without a body, then we are done */
        if (req->kind == EVHTTP_REQUEST && req->type != EVHTTP_REQ_POST) {
                evhttp_connection_done(evcon);
                return;
        }
        evcon->state = EVCON_READING_BODY;
        xfer_enc = evhttp_find_header(req->input_headers, "Transfer-Encoding");
        if (xfer_enc != NULL && strcasecmp(xfer_enc, "chunked") == 0) {
                req->chunked = 1;
                req->ntoread = -1;
        } else {
                if (evhttp_get_body_length(req) == -1) {
                        evhttp_connection_fail(evcon,
                            EVCON_HTTP_INVALID_HEADER);
                        return;
                }
        }
        evhttp_read_body(evcon, req);
}

static void
evhttp_read_firstline(struct evhttp_connection *evcon,
                      struct evhttp_request *req)
{
        enum message_read_status res;

        res = evhttp_parse_firstline(req, evcon->input_buffer);
        if (res == DATA_CORRUPTED) {
                /* Error while reading, terminate */
                event_debug(("%s: bad header lines on %d\n",
                        __func__, evcon->fd));
                evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER);
                return;
        } else if (res == MORE_DATA_EXPECTED) {
                /* Need more header lines */
                evhttp_add_event(&evcon->ev, 
                    evcon->timeout, HTTP_READ_TIMEOUT);
                return;
        }

        evcon->state = EVCON_READING_HEADERS;
        evhttp_read_header(evcon, req);
}

static void
evhttp_read_header(struct evhttp_connection *evcon, struct evhttp_request *req)
{
        enum message_read_status res;
        int fd = evcon->fd;

        res = evhttp_parse_headers(req, evcon->input_buffer);
        if (res == DATA_CORRUPTED) {
                /* Error while reading, terminate */
                event_debug(("%s: bad header lines on %d\n", __func__, fd));
                evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER);
                return;
        } else if (res == MORE_DATA_EXPECTED) {
                /* Need more header lines */
                evhttp_add_event(&evcon->ev, 
                    evcon->timeout, HTTP_READ_TIMEOUT);
                return;
        }

        /* Done reading headers, do the real work */
        switch (req->kind) {
        case EVHTTP_REQUEST:
                event_debug(("%s: checking for post data on %d\n",
                                __func__, fd));
                evhttp_get_body(evcon, req);
                break;

        case EVHTTP_RESPONSE:
                if (req->response_code == HTTP_NOCONTENT ||
                    req->response_code == HTTP_NOTMODIFIED ||
                    (req->response_code >= 100 && req->response_code < 200)) {
                        event_debug(("%s: skipping body for code %d\n",
                                        __func__, req->response_code));
                        evhttp_connection_done(evcon);
                } else {
                        event_debug(("%s: start of read body for %s on %d\n",
                                __func__, req->remote_host, fd));
                        evhttp_get_body(evcon, req);
                }
                break;

        default:
                event_warnx("%s: bad header on %d", __func__, fd);
                evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER);
                break;
        }
}

/*
 * Creates a TCP connection to the specified port and executes a callback
 * when finished.  Failure or sucess is indicate by the passed connection
 * object.
 *
 * Although this interface accepts a hostname, it is intended to take
 * only numeric hostnames so that non-blocking DNS resolution can
 * happen elsewhere.
 */

struct evhttp_connection *
evhttp_connection_new(const char *address, unsigned short port)
{
        struct evhttp_connection *evcon = NULL;
        
        event_debug(("Attempting connection to %s:%d\n", address, port));

        if ((evcon = calloc(1, sizeof(struct evhttp_connection))) == NULL) {
                event_warn("%s: calloc failed", __func__);
                goto error;
        }

        evcon->fd = -1;
        evcon->port = port;

        evcon->timeout = -1;
        evcon->retry_cnt = evcon->retry_max = 0;

        if ((evcon->address = strdup(address)) == NULL) {
                event_warn("%s: strdup failed", __func__);
                goto error;
        }

        if ((evcon->input_buffer = evbuffer_new()) == NULL) {
                event_warn("%s: evbuffer_new failed", __func__);
                goto error;
        }

        if ((evcon->output_buffer = evbuffer_new()) == NULL) {
                event_warn("%s: evbuffer_new failed", __func__);
                goto error;
        }
        
        evcon->state = EVCON_DISCONNECTED;
        TAILQ_INIT(&evcon->requests);

        return (evcon);
        
 error:
        if (evcon != NULL)
                evhttp_connection_free(evcon);
        return (NULL);
}

void evhttp_connection_set_base(struct evhttp_connection *evcon,
    struct event_base *base)
{
        assert(evcon->base == NULL);
        assert(evcon->state == EVCON_DISCONNECTED);
        evcon->base = base;
}

void
evhttp_connection_set_timeout(struct evhttp_connection *evcon,
    int timeout_in_secs)
{
        evcon->timeout = timeout_in_secs;
}

void
evhttp_connection_set_retries(struct evhttp_connection *evcon,
    int retry_max)
{
        evcon->retry_max = retry_max;
}

void
evhttp_connection_set_closecb(struct evhttp_connection *evcon,
    void (*cb)(struct evhttp_connection *, void *), void *cbarg)
{
        evcon->closecb = cb;
        evcon->closecb_arg = cbarg;
}

void
evhttp_connection_get_peer(struct evhttp_connection *evcon,
    char **address, u_short *port)
{
        *address = evcon->address;
        *port = evcon->port;
}

int
evhttp_connection_connect(struct evhttp_connection *evcon)
{
        if (evcon->state == EVCON_CONNECTING)
                return (0);
        
        evhttp_connection_reset(evcon);

        assert(!(evcon->flags & EVHTTP_CON_INCOMING));
        evcon->flags |= EVHTTP_CON_OUTGOING;
        
        evcon->fd = bind_socket(
                evcon->bind_address, evcon->bind_port, 0 /*reuse*/);
        if (evcon->fd == -1) {
                event_debug(("%s: failed to bind to \"%s\"",
                        __func__, evcon->bind_address));
                return (-1);
        }

        if (socket_connect(evcon->fd, evcon->address, evcon->port) == -1) {
                EVUTIL_CLOSESOCKET(evcon->fd); evcon->fd = -1;
                return (-1);
        }

        /* Set up a callback for successful connection setup */
        event_set(&evcon->ev, evcon->fd, EV_WRITE, evhttp_connectioncb, evcon);
        EVHTTP_BASE_SET(evcon, &evcon->ev);
        evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_CONNECT_TIMEOUT);

        evcon->state = EVCON_CONNECTING;
        
        return (0);
}

/*
 * Starts an HTTP request on the provided evhttp_connection object.
 * If the connection object is not connected to the web server already,
 * this will start the connection.
 */

int
evhttp_make_request(struct evhttp_connection *evcon,
    struct evhttp_request *req,
    enum evhttp_cmd_type type, const char *uri)
{
        /* We are making a request */
        req->kind = EVHTTP_REQUEST;
        req->type = type;
        if (req->uri != NULL)
                free(req->uri);
        if ((req->uri = strdup(uri)) == NULL)
                event_err(1, "%s: strdup", __func__);

        /* Set the protocol version if it is not supplied */
        if (!req->major && !req->minor) {
                req->major = 1;
                req->minor = 1;
        }
        
        assert(req->evcon == NULL);
        req->evcon = evcon;
        assert(!(req->flags & EVHTTP_REQ_OWN_CONNECTION));
        
        TAILQ_INSERT_TAIL(&evcon->requests, req, next);

        /* If the connection object is not connected; make it so */
        if (!evhttp_connected(evcon))
                return (evhttp_connection_connect(evcon));

        /*
         * If it's connected already and we are the first in the queue,
         * then we can dispatch this request immediately.  Otherwise, it
         * will be dispatched once the pending requests are completed.
         */
        if (TAILQ_FIRST(&evcon->requests) == req)
                evhttp_request_dispatch(evcon);

        return (0);
}

/*
 * Reads data from file descriptor into request structure
 * Request structure needs to be set up correctly.
 */

void
evhttp_start_read(struct evhttp_connection *evcon)
{
        /* Set up an event to read the headers */
        if (event_initialized(&evcon->ev))
                event_del(&evcon->ev);
        event_set(&evcon->ev, evcon->fd, EV_READ, evhttp_read, evcon);
        EVHTTP_BASE_SET(evcon, &evcon->ev);
        
        evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT);
        evcon->state = EVCON_READING_FIRSTLINE;
}

static void
evhttp_send_done(struct evhttp_connection *evcon, void *arg)
{
        int need_close;
        struct evhttp_request *req = TAILQ_FIRST(&evcon->requests);
        TAILQ_REMOVE(&evcon->requests, req, next);

        /* delete possible close detection events */
        evhttp_connection_stop_detectclose(evcon);
        
        need_close =
            (req->minor == 0 &&
                !evhttp_is_connection_keepalive(req->input_headers))||
            evhttp_is_connection_close(req->flags, req->input_headers) ||
            evhttp_is_connection_close(req->flags, req->output_headers);

        assert(req->flags & EVHTTP_REQ_OWN_CONNECTION);
        evhttp_request_free(req);

        if (need_close) {
                evhttp_connection_free(evcon);
                return;
        } 

        /* we have a persistent connection; try to accept another request. */
        if (evhttp_associate_new_request_with_connection(evcon) == -1)
                evhttp_connection_free(evcon);
}

/*
 * Returns an error page.
 */

void
evhttp_send_error(struct evhttp_request *req, int error, const char *reason)
{
#define ERR_FORMAT "<HTML><HEAD>\n" \
            "<TITLE>%d %s</TITLE>\n" \
            "</HEAD><BODY>\n" \
            "<H1>Method Not Implemented</H1>\n" \
            "Invalid method in request<P>\n" \
            "</BODY></HTML>\n"

        struct evbuffer *buf = evbuffer_new();

        /* close the connection on error */
        evhttp_add_header(req->output_headers, "Connection", "close");

        evhttp_response_code(req, error, reason);

        evbuffer_add_printf(buf, ERR_FORMAT, error, reason);

        evhttp_send_page(req, buf);

        evbuffer_free(buf);
#undef ERR_FORMAT
}

/* Requires that headers and response code are already set up */

static inline void
evhttp_send(struct evhttp_request *req, struct evbuffer *databuf)
{
        struct evhttp_connection *evcon = req->evcon;

        assert(TAILQ_FIRST(&evcon->requests) == req);

        /* xxx: not sure if we really should expose the data buffer this way */
        if (databuf != NULL)
                evbuffer_add_buffer(req->output_buffer, databuf);
        
        /* Adds headers to the response */
        evhttp_make_header(evcon, req);

        evhttp_write_buffer(evcon, evhttp_send_done, NULL);
}

void
evhttp_send_reply(struct evhttp_request *req, int code, const char *reason,
    struct evbuffer *databuf)
{
        evhttp_response_code(req, code, reason);
        
        evhttp_send(req, databuf);
}

void
evhttp_send_reply_start(struct evhttp_request *req, int code,
    const char *reason)
{
        evhttp_response_code(req, code, reason);
        if (req->major == 1 && req->minor == 1) {
                /* use chunked encoding for HTTP/1.1 */
                evhttp_add_header(req->output_headers, "Transfer-Encoding",
                    "chunked");
                req->chunked = 1;
        }
        evhttp_make_header(req->evcon, req);
        evhttp_write_buffer(req->evcon, NULL, NULL);
}

void
evhttp_send_reply_chunk(struct evhttp_request *req, struct evbuffer *databuf)
{
        if (req->chunked) {
                evbuffer_add_printf(req->evcon->output_buffer, "%x\r\n",
                                    (unsigned)EVBUFFER_LENGTH(databuf));
        }
        evbuffer_add_buffer(req->evcon->output_buffer, databuf);
        if (req->chunked) {
                evbuffer_add(req->evcon->output_buffer, "\r\n", 2);
        }
        evhttp_write_buffer(req->evcon, NULL, NULL);
}

void
evhttp_send_reply_end(struct evhttp_request *req)
{
        struct evhttp_connection *evcon = req->evcon;

        if (req->chunked) {
                evbuffer_add(req->evcon->output_buffer, "0\r\n\r\n", 5);
                evhttp_write_buffer(req->evcon, evhttp_send_done, NULL);
                req->chunked = 0;
        } else if (!event_pending(&evcon->ev, EV_WRITE|EV_TIMEOUT, NULL)) {
                /* let the connection know that we are done with the request */
                evhttp_send_done(evcon, NULL);
        } else {
                /* make the callback execute after all data has been written */
                evcon->cb = evhttp_send_done;
                evcon->cb_arg = NULL;
        }
}

void
evhttp_response_code(struct evhttp_request *req, int code, const char *reason)
{
        req->kind = EVHTTP_RESPONSE;
        req->response_code = code;
        if (req->response_code_line != NULL)
                free(req->response_code_line);
        req->response_code_line = strdup(reason);
}

void
evhttp_send_page(struct evhttp_request *req, struct evbuffer *databuf)
{
        if (!req->major || !req->minor) {
                req->major = 1;
                req->minor = 1;
        }
        
        if (req->kind != EVHTTP_RESPONSE)
                evhttp_response_code(req, 200, "OK");

        evhttp_clear_headers(req->output_headers);
        evhttp_add_header(req->output_headers, "Content-Type", "text/html");
        evhttp_add_header(req->output_headers, "Connection", "close");

        evhttp_send(req, databuf);
}

static const char uri_chars[256] = {
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 1, 0, 0, 1, 0, 0, 1,   1, 1, 1, 1, 1, 1, 1, 1,
        1, 1, 1, 1, 1, 1, 1, 1,   1, 1, 1, 0, 0, 1, 0, 0,
        /* 64 */
        1, 1, 1, 1, 1, 1, 1, 1,   1, 1, 1, 1, 1, 1, 1, 1,
        1, 1, 1, 1, 1, 1, 1, 1,   1, 1, 1, 0, 0, 0, 0, 1,
        0, 1, 1, 1, 1, 1, 1, 1,   1, 1, 1, 1, 1, 1, 1, 1,
        1, 1, 1, 1, 1, 1, 1, 1,   1, 1, 1, 0, 0, 0, 1, 0,
        /* 128 */
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        /* 192 */
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0,   0, 0, 0, 0, 0, 0, 0, 0,
};

/*
 * Helper functions to encode/decode a URI.
 * The returned string must be freed by the caller.
 */
char *
evhttp_encode_uri(const char *uri)
{
        struct evbuffer *buf = evbuffer_new();
        char *p;

        for (p = (char *)uri; *p != '\0'; p++) {
                if (uri_chars[(u_char)(*p)]) {
                        evbuffer_add(buf, p, 1);
                } else {
                        evbuffer_add_printf(buf, "%%%02X", (u_char)(*p));
                }
        }
        evbuffer_add(buf, "", 1);
        p = strdup((char *)EVBUFFER_DATA(buf));
        evbuffer_free(buf);
        
        return (p);
}

/*
 * @param always_decode_plus: when true we transform plus to space even
 *     if we have not seen a ?.
 */
static int
evhttp_decode_uri_internal(
        const char *uri, size_t length, char *ret, int always_decode_plus)
{
        char c;
        int i, j, in_query = always_decode_plus;
        
        for (i = j = 0; uri[i] != '\0'; i++) {
                c = uri[i];
                if (c == '?') {
                        in_query = 1;
                } else if (c == '+' && in_query) {
                        c = ' ';
                } else if (c == '%' && isxdigit((unsigned char)uri[i+1]) &&
                    isxdigit((unsigned char)uri[i+2])) {
                        char tmp[] = { uri[i+1], uri[i+2], '\0' };
                        c = (char)strtol(tmp, NULL, 16);
                        i += 2;
                }
                ret[j++] = c;
        }
        ret[j] = '\0';

        return (j);
}

char *
evhttp_decode_uri(const char *uri)
{
        char *ret;

        if ((ret = malloc(strlen(uri) + 1)) == NULL)
                event_err(1, "%s: malloc(%lu)", __func__,
                          (unsigned long)(strlen(uri) + 1));

        evhttp_decode_uri_internal(uri, strlen(uri),
            ret, 0 /*always_decode_plus*/);

        return (ret);
}

/* 
 * Helper function to parse out arguments in a query.
 * The arguments are separated by key and value.
 */

void
evhttp_parse_query(const char *uri, struct evkeyvalq *headers)
{
        char *line;
        char *argument;
        char *p;

        TAILQ_INIT(headers);

        /* No arguments - we are done */
        if (strchr(uri, '?') == NULL)
                return;

        if ((line = strdup(uri)) == NULL)
                event_err(1, "%s: strdup", __func__);


        argument = line;

        /* We already know that there has to be a ? */
        strsep(&argument, "?");

        p = argument;
        while (p != NULL && *p != '\0') {
                char *key, *value, *decoded_value;
                argument = strsep(&p, "&");

                value = argument;
                key = strsep(&value, "=");
                if (value == NULL)
                        goto error;

                if ((decoded_value = malloc(strlen(value) + 1)) == NULL)
                        event_err(1, "%s: malloc", __func__);

                evhttp_decode_uri_internal(value, strlen(value),
                    decoded_value, 1 /*always_decode_plus*/);
                event_debug(("Query Param: %s -> %s\n", key, decoded_value));
                evhttp_add_header_internal(headers, key, decoded_value);
                free(decoded_value);
        }

 error:
        free(line);
}

static struct evhttp_cb *
evhttp_dispatch_callback(struct httpcbq *callbacks, struct evhttp_request *req)
{
        struct evhttp_cb *cb;
        size_t offset = 0;

        /* Test for different URLs */
        char *p = strchr(req->uri, '?');
        if (p != NULL)
                offset = (size_t)(p - req->uri);

        TAILQ_FOREACH(cb, callbacks, next) {
                int res = 0;
                if (p == NULL) {
                        res = strcmp(cb->what, req->uri) == 0;
                } else {
                        res = ((strncmp(cb->what, req->uri, offset) == 0) &&
                                        (cb->what[offset] == '\0'));
                }

                if (res)
                        return (cb);
        }

        return (NULL);
}

static void
evhttp_handle_request(struct evhttp_request *req, void *arg)
{
        struct evhttp *http = arg;
        struct evhttp_cb *cb = NULL;

        if (req->uri == NULL) {
                evhttp_send_error(req, HTTP_BADREQUEST, "Bad Request");
                return;
        }

        if ((cb = evhttp_dispatch_callback(&http->callbacks, req)) != NULL) {
                (*cb->cb)(req, cb->cbarg);
                return;
        }

        /* Generic call back */
        if (http->gencb) {
                (*http->gencb)(req, http->gencbarg);
                return;
        } else {
                /* We need to send a 404 here */
#define ERR_FORMAT "<html><head>" \
                    "<title>404 Not Found</title>" \
                    "</head><body>" \
                    "<h1>Not Found</h1>" \
                    "<p>The requested URL %s was not found on this server.</p>"\
                    "</body></html>\n"

                char *escaped_html = evhttp_htmlescape(req->uri);
                struct evbuffer *buf = evbuffer_new();

                evhttp_response_code(req, HTTP_NOTFOUND, "Not Found");

                evbuffer_add_printf(buf, ERR_FORMAT, escaped_html);

                free(escaped_html);

                evhttp_send_page(req, buf);

                evbuffer_free(buf);
#undef ERR_FORMAT
        }
}

static void
accept_socket(int fd, short what, void *arg)
{
        struct evhttp *http = arg;
        struct sockaddr_storage ss;
        socklen_t addrlen = sizeof(ss);
        int nfd;

        if ((nfd = accept(fd, (struct sockaddr *)&ss, &addrlen)) == -1) {
                if (errno != EAGAIN && errno != EINTR)
                        event_warn("%s: bad accept", __func__);
                return;
        }
        if (evutil_make_socket_nonblocking(nfd) < 0)
                return;

        evhttp_get_request(http, nfd, (struct sockaddr *)&ss, addrlen);
}

int
evhttp_bind_socket(struct evhttp *http, const char *address, u_short port)
{
        int fd;
        int res;

        if ((fd = bind_socket(address, port, 1 /*reuse*/)) == -1)
                return (-1);

        if (listen(fd, 128) == -1) {
                event_warn("%s: listen", __func__);
                EVUTIL_CLOSESOCKET(fd);
                return (-1);
        }

        res = evhttp_accept_socket(http, fd);
        
        if (res != -1)
                event_debug(("Bound to port %d - Awaiting connections ... ",
                        port));

        return (res);
}

int
evhttp_accept_socket(struct evhttp *http, int fd)
{
        struct evhttp_bound_socket *bound;
        struct event *ev;
        int res;

        bound = malloc(sizeof(struct evhttp_bound_socket));
        if (bound == NULL)
                return (-1);

        ev = &bound->bind_ev;

        /* Schedule the socket for accepting */
        event_set(ev, fd, EV_READ | EV_PERSIST, accept_socket, http);
        EVHTTP_BASE_SET(http, ev);

        res = event_add(ev, NULL);

        if (res == -1) {
                free(bound);
                return (-1);
        }

        TAILQ_INSERT_TAIL(&http->sockets, bound, next);

        return (0);
}

static struct evhttp*
evhttp_new_object(void)
{
        struct evhttp *http = NULL;

        if ((http = calloc(1, sizeof(struct evhttp))) == NULL) {
                event_warn("%s: calloc", __func__);
                return (NULL);
        }

        http->timeout = -1;

        TAILQ_INIT(&http->sockets);
        TAILQ_INIT(&http->callbacks);
        TAILQ_INIT(&http->connections);

        return (http);
}

struct evhttp *
evhttp_new(struct event_base *base)
{
        struct evhttp *http = evhttp_new_object();

        http->base = base;

        return (http);
}

/*
 * Start a web server on the specified address and port.
 */

struct evhttp *
evhttp_start(const char *address, u_short port)
{
        struct evhttp *http = evhttp_new_object();

        if (evhttp_bind_socket(http, address, port) == -1) {
                free(http);
                return (NULL);
        }

        return (http);
}

void
evhttp_free(struct evhttp* http)
{
        struct evhttp_cb *http_cb;
        struct evhttp_connection *evcon;
        struct evhttp_bound_socket *bound;
        int fd;

        /* Remove the accepting part */
        while ((bound = TAILQ_FIRST(&http->sockets)) != NULL) {
                TAILQ_REMOVE(&http->sockets, bound, next);

                fd = bound->bind_ev.ev_fd;
                event_del(&bound->bind_ev);
                EVUTIL_CLOSESOCKET(fd);

                free(bound);
        }

        while ((evcon = TAILQ_FIRST(&http->connections)) != NULL) {
                /* evhttp_connection_free removes the connection */
                evhttp_connection_free(evcon);
        }

        while ((http_cb = TAILQ_FIRST(&http->callbacks)) != NULL) {
                TAILQ_REMOVE(&http->callbacks, http_cb, next);
                free(http_cb->what);
                free(http_cb);
        }
        
        free(http);
}

void
evhttp_set_timeout(struct evhttp* http, int timeout_in_secs)
{
        http->timeout = timeout_in_secs;
}

void
evhttp_set_cb(struct evhttp *http, const char *uri,
    void (*cb)(struct evhttp_request *, void *), void *cbarg)
{
        struct evhttp_cb *http_cb;

        if ((http_cb = calloc(1, sizeof(struct evhttp_cb))) == NULL)
                event_err(1, "%s: calloc", __func__);

        http_cb->what = strdup(uri);
        http_cb->cb = cb;
        http_cb->cbarg = cbarg;

        TAILQ_INSERT_TAIL(&http->callbacks, http_cb, next);
}

int
evhttp_del_cb(struct evhttp *http, const char *uri)
{
        struct evhttp_cb *http_cb;

        TAILQ_FOREACH(http_cb, &http->callbacks, next) {
                if (strcmp(http_cb->what, uri) == 0)
                        break;
        }
        if (http_cb == NULL)
                return (-1);

        TAILQ_REMOVE(&http->callbacks, http_cb, next);
        free(http_cb->what);
        free(http_cb);

        return (0);
}

void
evhttp_set_gencb(struct evhttp *http,
    void (*cb)(struct evhttp_request *, void *), void *cbarg)
{
        http->gencb = cb;
        http->gencbarg = cbarg;
}

/*
 * Request related functions
 */

struct evhttp_request *
evhttp_request_new(void (*cb)(struct evhttp_request *, void *), void *arg)
{
        struct evhttp_request *req = NULL;

        /* Allocate request structure */
        if ((req = calloc(1, sizeof(struct evhttp_request))) == NULL) {
                event_warn("%s: calloc", __func__);
                goto error;
        }

        req->kind = EVHTTP_RESPONSE;
        req->input_headers = calloc(1, sizeof(struct evkeyvalq));
        if (req->input_headers == NULL) {
                event_warn("%s: calloc", __func__);
                goto error;
        }
        TAILQ_INIT(req->input_headers);

        req->output_headers = calloc(1, sizeof(struct evkeyvalq));
        if (req->output_headers == NULL) {
                event_warn("%s: calloc", __func__);
                goto error;
        }
        TAILQ_INIT(req->output_headers);

        if ((req->input_buffer = evbuffer_new()) == NULL) {
                event_warn("%s: evbuffer_new", __func__);
                goto error;
        }

        if ((req->output_buffer = evbuffer_new()) == NULL) {
                event_warn("%s: evbuffer_new", __func__);
                goto error;
        }

        req->cb = cb;
        req->cb_arg = arg;

        return (req);

 error:
        if (req != NULL)
                evhttp_request_free(req);
        return (NULL);
}

void
evhttp_request_free(struct evhttp_request *req)
{
        if (req->remote_host != NULL)
                free(req->remote_host);
        if (req->uri != NULL)
                free(req->uri);
        if (req->response_code_line != NULL)
                free(req->response_code_line);

        evhttp_clear_headers(req->input_headers);
        free(req->input_headers);

        evhttp_clear_headers(req->output_headers);
        free(req->output_headers);

        if (req->input_buffer != NULL)
                evbuffer_free(req->input_buffer);

        if (req->output_buffer != NULL)
                evbuffer_free(req->output_buffer);

        free(req);
}

void
evhttp_request_set_chunked_cb(struct evhttp_request *req,
    void (*cb)(struct evhttp_request *, void *))
{
        req->chunk_cb = cb;
}

/*
 * Allows for inspection of the request URI
 */

const char *
evhttp_request_uri(struct evhttp_request *req) {
        if (req->uri == NULL)
                event_debug(("%s: request %p has no uri\n", __func__, req));
        return (req->uri);
}

/*
 * Takes a file descriptor to read a request from.
 * The callback is executed once the whole request has been read.
 */

static struct evhttp_connection*
evhttp_get_request_connection(
        struct evhttp* http,
        int fd, struct sockaddr *sa, socklen_t salen)
{
        struct evhttp_connection *evcon;
        char *hostname = NULL, *portname = NULL;

        name_from_addr(sa, salen, &hostname, &portname);
        if (hostname == NULL || portname == NULL) {
                if (hostname) free(hostname);
                if (portname) free(portname);
                return (NULL);
        }

        event_debug(("%s: new request from %s:%s on %d\n",
                        __func__, hostname, portname, fd));

        /* we need a connection object to put the http request on */
        evcon = evhttp_connection_new(hostname, atoi(portname));
        free(hostname);
        free(portname);
        if (evcon == NULL)
                return (NULL);

        /* associate the base if we have one*/
        evhttp_connection_set_base(evcon, http->base);

        evcon->flags |= EVHTTP_CON_INCOMING;
        evcon->state = EVCON_READING_FIRSTLINE;
        
        evcon->fd = fd;

        return (evcon);
}

static int
evhttp_associate_new_request_with_connection(struct evhttp_connection *evcon)
{
        struct evhttp *http = evcon->http_server;
        struct evhttp_request *req;
        if ((req = evhttp_request_new(evhttp_handle_request, http)) == NULL)
                return (-1);

        req->evcon = evcon;     /* the request ends up owning the connection */
        req->flags |= EVHTTP_REQ_OWN_CONNECTION;
        
        TAILQ_INSERT_TAIL(&evcon->requests, req, next);
        
        req->kind = EVHTTP_REQUEST;
        
        if ((req->remote_host = strdup(evcon->address)) == NULL)
                event_err(1, "%s: strdup", __func__);
        req->remote_port = evcon->port;

        evhttp_start_read(evcon);
        
        return (0);
}

void
evhttp_get_request(struct evhttp *http, int fd,
    struct sockaddr *sa, socklen_t salen)
{
        struct evhttp_connection *evcon;

        evcon = evhttp_get_request_connection(http, fd, sa, salen);
        if (evcon == NULL)
                return;

        /* the timeout can be used by the server to close idle connections */
        if (http->timeout != -1)
                evhttp_connection_set_timeout(evcon, http->timeout);

        /* 
         * if we want to accept more than one request on a connection,
         * we need to know which http server it belongs to.
         */
        evcon->http_server = http;
        TAILQ_INSERT_TAIL(&http->connections, evcon, next);
        
        if (evhttp_associate_new_request_with_connection(evcon) == -1)
                evhttp_connection_free(evcon);
}


/*
 * Network helper functions that we do not want to export to the rest of
 * the world.
 */
#if 0 /* Unused */
static struct addrinfo *
addr_from_name(char *address)
{
#ifdef HAVE_GETADDRINFO
        struct addrinfo ai, *aitop;
        int ai_result;

        memset(&ai, 0, sizeof(ai));
        ai.ai_family = AF_INET;
        ai.ai_socktype = SOCK_RAW;
        ai.ai_flags = 0;
        if ((ai_result = getaddrinfo(address, NULL, &ai, &aitop)) != 0) {
                if ( ai_result == EAI_SYSTEM )
                        event_warn("getaddrinfo");
                else
                        event_warnx("getaddrinfo: %s", gai_strerror(ai_result));
        }

        return (aitop);
#else
        assert(0);
        return NULL; /* XXXXX Use gethostbyname, if this function is ever used. */
#endif
}
#endif

static void
name_from_addr(struct sockaddr *sa, socklen_t salen,
    char **phost, char **pport)
{
        char ntop[NI_MAXHOST];
        char strport[NI_MAXSERV];
        int ni_result;

#ifdef HAVE_GETNAMEINFO
        ni_result = getnameinfo(sa, salen,
                ntop, sizeof(ntop), strport, sizeof(strport),
                NI_NUMERICHOST|NI_NUMERICSERV);
        
        if (ni_result != 0) {
                if (ni_result == EAI_SYSTEM)
                        event_err(1, "getnameinfo failed");
                else
                        event_errx(1, "getnameinfo failed: %s", gai_strerror(ni_result));
                return;
        }
#else
        ni_result = fake_getnameinfo(sa, salen,
                ntop, sizeof(ntop), strport, sizeof(strport),
                NI_NUMERICHOST|NI_NUMERICSERV);
        if (ni_result != 0)
                        return;
#endif
        *phost = strdup(ntop);
        *pport = strdup(strport);
}

/* Create a non-blocking socket and bind it */
/* todo: rename this function */
static int
bind_socket_ai(struct addrinfo *ai, int reuse)
{
        int fd, on = 1, r;
        int serrno;

        /* Create listen socket */
        fd = socket(AF_INET, SOCK_STREAM, 0);
        if (fd == -1) {
                event_warn("socket");
                return (-1);
        }

        if (evutil_make_socket_nonblocking(fd) < 0)
                goto out;

#ifndef WIN32
        if (fcntl(fd, F_SETFD, 1) == -1) {
                event_warn("fcntl(F_SETFD)");
                goto out;
        }
#endif

        setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, sizeof(on));
        if (reuse) {
                setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
                    (void *)&on, sizeof(on));
        }

        if (ai != NULL) {
                r = bind(fd, ai->ai_addr, ai->ai_addrlen);
                if (r == -1)
                        goto out;
        }

        return (fd);

 out:
        serrno = EVUTIL_SOCKET_ERROR();
        EVUTIL_CLOSESOCKET(fd);
        EVUTIL_SET_SOCKET_ERROR(serrno);
        return (-1);
}

static struct addrinfo *
make_addrinfo(const char *address, u_short port)
{
        struct addrinfo *aitop = NULL;

#ifdef HAVE_GETADDRINFO
        struct addrinfo ai;
        char strport[NI_MAXSERV];
        int ai_result;

        memset(&ai, 0, sizeof(ai));
        ai.ai_family = AF_INET;
        ai.ai_socktype = SOCK_STREAM;
        ai.ai_flags = AI_PASSIVE;  /* turn NULL host name into INADDR_ANY */
        evutil_snprintf(strport, sizeof(strport), "%d", port);
        if ((ai_result = getaddrinfo(address, strport, &ai, &aitop)) != 0) {
                if ( ai_result == EAI_SYSTEM )
                        event_warn("getaddrinfo");
                else
                        event_warnx("getaddrinfo: %s", gai_strerror(ai_result));
                return (NULL);
        }
#else
        static int cur;
        static struct addrinfo ai[2]; /* We will be returning the address of some of this memory so it has to last even after this call. */
        if (++cur == 2) cur = 0;   /* allow calling this function twice */

        if (fake_getaddrinfo(address, &ai[cur]) < 0) {
                event_warn("fake_getaddrinfo");
                return (NULL);
        }
        aitop = &ai[cur];
        ((struct sockaddr_in *) aitop->ai_addr)->sin_port = htons(port);
#endif

        return (aitop);
}

static int
bind_socket(const char *address, u_short port, int reuse)
{
        int fd;
        struct addrinfo *aitop = NULL;

        /* just create an unbound socket */
        if (address == NULL && port == 0)
                return bind_socket_ai(NULL, 0);
                
        aitop = make_addrinfo(address, port);

        if (aitop == NULL)
                return (-1);

        fd = bind_socket_ai(aitop, reuse);

#ifdef HAVE_GETADDRINFO
        freeaddrinfo(aitop);
#else
        fake_freeaddrinfo(aitop);
#endif

        return (fd);
}

static int
socket_connect(int fd, const char *address, unsigned short port)
{
        struct addrinfo *ai = make_addrinfo(address, port);
        int res = -1;

        if (ai == NULL) {
                event_debug(("%s: make_addrinfo: \"%s:%d\"",
                        __func__, address, port));
                return (-1);
        }

        if (connect(fd, ai->ai_addr, ai->ai_addrlen) == -1) {
#ifdef WIN32
                int tmp_error = WSAGetLastError();
                if (tmp_error != WSAEWOULDBLOCK && tmp_error != WSAEINVAL &&
                    tmp_error != WSAEINPROGRESS) {
                        goto out;
                }
#else
                if (errno != EINPROGRESS) {
                        goto out;
                }
#endif
        }

        /* everything is fine */
        res = 0;

out:
#ifdef HAVE_GETADDRINFO
        freeaddrinfo(ai);
#else
        fake_freeaddrinfo(ai);
#endif

        return (res);
}