root/remote-testsvn.c

DEFINITIONS

1. cmd_capabilities
2. terminate_batch
3. read_ref_note
4. parse_rev_note
5. note2mark_cb
6. regenerate_marks
7. check_or_regenerate_marks
8. cmd_import
9. cmd_list
10. do_command
11. main

#include "cache.h"
#include "refs.h"
#include "remote.h"
#include "strbuf.h"
#include "url.h"
#include "exec_cmd.h"
#include "run-command.h"
#include "vcs-svn/svndump.h"
#include "notes.h"
#include "argv-array.h"

static const char *url;
static int dump_from_file;
static const char *private_ref;
static const char *remote_ref = "refs/heads/master";
static const char *marksfilename, *notes_ref;
struct rev_note { unsigned int rev_nr; };

static int cmd_capabilities(const char *line);
static int cmd_import(const char *line);
static int cmd_list(const char *line);

typedef int (*input_command_handler)(const char *);
struct input_command_entry {
        const char *name;
        input_command_handler fn;
        unsigned char batchable;        /* whether the command starts or is part of a batch */
};

static const struct input_command_entry input_command_list[] = {
        { "capabilities", cmd_capabilities, 0 },
        { "import", cmd_import, 1 },
        { "list", cmd_list, 0 },
        { NULL, NULL }
};

static int cmd_capabilities(const char *line)
{
        printf("import\n");
        printf("bidi-import\n");
        printf("refspec %s:%s\n\n", remote_ref, private_ref);
        fflush(stdout);
        return 0;
}

static void terminate_batch(void)
{
        /* terminate a current batch's fast-import stream */
        printf("done\n");
        fflush(stdout);
}

/* NOTE: 'ref' refers to a git reference, while 'rev' refers to a svn revision. */
static char *read_ref_note(const unsigned char sha1[20])
{
        const unsigned char *note_sha1;
        char *msg = NULL;
        unsigned long msglen;
        enum object_type type;

        init_notes(NULL, notes_ref, NULL, 0);
        if (!(note_sha1 = get_note(NULL, sha1)))
                return NULL;    /* note tree not found */
        if (!(msg = read_sha1_file(note_sha1, &type, &msglen)))
                error("Empty notes tree. %s", notes_ref);
        else if (!msglen || type != OBJ_BLOB) {
                error("Note contains unusable content. "
                        "Is something else using this notes tree? %s", notes_ref);
                free(msg);
                msg = NULL;
        }
        free_notes(NULL);
        return msg;
}

static int parse_rev_note(const char *msg, struct rev_note *res)
{
        const char *key, *value, *end;
        size_t len;

        while (*msg) {
                end = strchrnul(msg, '\n');
                len = end - msg;

                key = "Revision-number: ";
                if (starts_with(msg, key)) {
                        long i;
                        char *end;
                        value = msg + strlen(key);
                        i = strtol(value, &end, 0);
                        if (end == value || i < 0 || i > UINT32_MAX)
                                return -1;
                        res->rev_nr = i;
                        return 0;
                }
                msg += len + 1;
        }
        /* didn't find it */
        return -1;
}

static int note2mark_cb(const unsigned char *object_sha1,
                const unsigned char *note_sha1, char *note_path,
                void *cb_data)
{
        FILE *file = (FILE *)cb_data;
        char *msg;
        unsigned long msglen;
        enum object_type type;
        struct rev_note note;

        if (!(msg = read_sha1_file(note_sha1, &type, &msglen)) ||
                        !msglen || type != OBJ_BLOB) {
                free(msg);
                return 1;
        }
        if (parse_rev_note(msg, &note))
                return 2;
        if (fprintf(file, ":%d %s\n", note.rev_nr, sha1_to_hex(object_sha1)) < 1)
                return 3;
        return 0;
}

static void regenerate_marks(void)
{
        int ret;
        FILE *marksfile = fopen(marksfilename, "w+");

        if (!marksfile)
                die_errno("Couldn't create mark file %s.", marksfilename);
        ret = for_each_note(NULL, 0, note2mark_cb, marksfile);
        if (ret)
                die("Regeneration of marks failed, returned %d.", ret);
        fclose(marksfile);
}

static void check_or_regenerate_marks(int latestrev)
{
        FILE *marksfile;
        struct strbuf sb = STRBUF_INIT;
        struct strbuf line = STRBUF_INIT;
        int found = 0;

        if (latestrev < 1)
                return;

        init_notes(NULL, notes_ref, NULL, 0);
        marksfile = fopen(marksfilename, "r");
        if (!marksfile) {
                regenerate_marks();
                marksfile = fopen(marksfilename, "r");
                if (!marksfile)
                        die_errno("cannot read marks file %s!", marksfilename);
                fclose(marksfile);
        } else {
                strbuf_addf(&sb, ":%d ", latestrev);
                while (strbuf_getline(&line, marksfile, '\n') != EOF) {
                        if (starts_with(line.buf, sb.buf)) {
                                found++;
                                break;
                        }
                }
                fclose(marksfile);
                if (!found)
                        regenerate_marks();
        }
        free_notes(NULL);
        strbuf_release(&sb);
        strbuf_release(&line);
}

static int cmd_import(const char *line)
{
        int code;
        int dumpin_fd;
        char *note_msg;
        unsigned char head_sha1[20];
        unsigned int startrev;
        struct child_process svndump_proc = CHILD_PROCESS_INIT;
        const char *command = "svnrdump";

        if (read_ref(private_ref, head_sha1))
                startrev = 0;
        else {
                note_msg = read_ref_note(head_sha1);
                if(note_msg == NULL) {
                        warning("No note found for %s.", private_ref);
                        startrev = 0;
                } else {
                        struct rev_note note = { 0 };
                        if (parse_rev_note(note_msg, &note))
                                die("Revision number couldn't be parsed from note.");
                        startrev = note.rev_nr + 1;
                        free(note_msg);
                }
        }
        check_or_regenerate_marks(startrev - 1);

        if (dump_from_file) {
                dumpin_fd = open(url, O_RDONLY);
                if(dumpin_fd < 0)
                        die_errno("Couldn't open svn dump file %s.", url);
        } else {
                svndump_proc.out = -1;
                argv_array_push(&svndump_proc.args, command);
                argv_array_push(&svndump_proc.args, "dump");
                argv_array_push(&svndump_proc.args, url);
                argv_array_pushf(&svndump_proc.args, "-r%u:HEAD", startrev);

                code = start_command(&svndump_proc);
                if (code)
                        die("Unable to start %s, code %d", command, code);
                dumpin_fd = svndump_proc.out;
        }
        /* setup marks file import/export */
        printf("feature import-marks-if-exists=%s\n"
                        "feature export-marks=%s\n", marksfilename, marksfilename);

        svndump_init_fd(dumpin_fd, STDIN_FILENO);
        svndump_read(url, private_ref, notes_ref);
        svndump_deinit();
        svndump_reset();

        close(dumpin_fd);
        if (!dump_from_file) {
                code = finish_command(&svndump_proc);
                if (code)
                        warning("%s, returned %d", command, code);
        }

        return 0;
}

static int cmd_list(const char *line)
{
        printf("? %s\n\n", remote_ref);
        fflush(stdout);
        return 0;
}

static int do_command(struct strbuf *line)
{
        const struct input_command_entry *p = input_command_list;
        static struct string_list batchlines = STRING_LIST_INIT_DUP;
        static const struct input_command_entry *batch_cmd;
        /*
         * commands can be grouped together in a batch.
         * Batches are ended by \n. If no batch is active the program ends.
         * During a batch all lines are buffered and passed to the handler function
         * when the batch is terminated.
         */
        if (line->len == 0) {
                if (batch_cmd) {
                        struct string_list_item *item;
                        for_each_string_list_item(item, &batchlines)
                                batch_cmd->fn(item->string);
                        terminate_batch();
                        batch_cmd = NULL;
                        string_list_clear(&batchlines, 0);
                        return 0;       /* end of the batch, continue reading other commands. */
                }
                return 1;       /* end of command stream, quit */
        }
        if (batch_cmd) {
                if (!starts_with(batch_cmd->name, line->buf))
                        die("Active %s batch interrupted by %s", batch_cmd->name, line->buf);
                /* buffer batch lines */
                string_list_append(&batchlines, line->buf);
                return 0;
        }

        for (p = input_command_list; p->name; p++) {
                if (starts_with(line->buf, p->name) && (strlen(p->name) == line->len ||
                                line->buf[strlen(p->name)] == ' ')) {
                        if (p->batchable) {
                                batch_cmd = p;
                                string_list_append(&batchlines, line->buf);
                                return 0;
                        }
                        return p->fn(line->buf);
                }
        }
        die("Unknown command '%s'\n", line->buf);
        return 0;
}

int main(int argc, char **argv)
{
        struct strbuf buf = STRBUF_INIT, url_sb = STRBUF_INIT,
                        private_ref_sb = STRBUF_INIT, marksfilename_sb = STRBUF_INIT,
                        notes_ref_sb = STRBUF_INIT;
        static struct remote *remote;
        const char *url_in;

        git_extract_argv0_path(argv[0]);
        setup_git_directory();
        if (argc < 2 || argc > 3) {
                usage("git-remote-svn <remote-name> [<url>]");
                return 1;
        }

        remote = remote_get(argv[1]);
        url_in = (argc == 3) ? argv[2] : remote->url[0];

        if (starts_with(url_in, "file://")) {
                dump_from_file = 1;
                url = url_decode(url_in + sizeof("file://")-1);
        } else {
                dump_from_file = 0;
                end_url_with_slash(&url_sb, url_in);
                url = url_sb.buf;
        }

        strbuf_addf(&private_ref_sb, "refs/svn/%s/master", remote->name);
        private_ref = private_ref_sb.buf;

        strbuf_addf(&notes_ref_sb, "refs/notes/%s/revs", remote->name);
        notes_ref = notes_ref_sb.buf;

        strbuf_addf(&marksfilename_sb, "%s/info/fast-import/remote-svn/%s.marks",
                get_git_dir(), remote->name);
        marksfilename = marksfilename_sb.buf;

        while (1) {
                if (strbuf_getline(&buf, stdin, '\n') == EOF) {
                        if (ferror(stdin))
                                die("Error reading command stream");
                        else
                                die("Unexpected end of command stream");
                }
                if (do_command(&buf))
                        break;
                strbuf_reset(&buf);
        }

        strbuf_release(&buf);
        strbuf_release(&url_sb);
        strbuf_release(&private_ref_sb);
        strbuf_release(&notes_ref_sb);
        strbuf_release(&marksfilename_sb);
        return 0;
}