root/ext/fileinfo/libmagic/funcs.c

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DEFINITIONS

This source file includes following definitions.
  1. FILE_RCSID
  2. file_error_core
  3. file_error
  4. file_magerror
  5. file_oomem
  6. file_badseek
  7. file_badread
  8. file_buffer
  9. file_reset
  10. file_getbuffer
  11. file_check_mem
  12. file_printedlen
  13. file_replace

/*
 * Copyright (c) Christos Zoulas 2003.
 * 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 immediately at the beginning of the file, without modification,
 *    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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */
#include "file.h"

#ifndef lint
FILE_RCSID("@(#)$File: funcs.c,v 1.61 2012/10/30 23:11:51 christos Exp $")
#endif  /* lint */

#include "magic.h"
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#if defined(HAVE_WCHAR_H)
#include <wchar.h>
#endif
#if defined(HAVE_WCTYPE_H)
#include <wctype.h>
#endif

#ifndef SIZE_MAX 
# define SIZE_MAX ((size_t) -1) 
#endif

#ifndef PREG_OFFSET_CAPTURE
# define PREG_OFFSET_CAPTURE                 (1<<8)
#endif

extern public void convert_libmagic_pattern(zval *pattern, int options);

/*
 * Like printf, only we append to a buffer.
 */
protected int
file_printf(struct magic_set *ms, const char *fmt, ...)
{
        va_list ap;
        int len;
        char *buf = NULL, *newstr;

        va_start(ap, fmt);
        len = vspprintf(&buf, 0, fmt, ap);
        va_end(ap);

        if (ms->o.buf != NULL) {
                len = spprintf(&newstr, 0, "%s%s", ms->o.buf, (buf ? buf : ""));
                if (buf) {
                        efree(buf);
                }
                efree(ms->o.buf);
                ms->o.buf = newstr;
        } else {
                ms->o.buf = buf;
        }
        return 0;
}

/*
 * error - print best error message possible
 */
/*VARARGS*/
private void
file_error_core(struct magic_set *ms, int error, const char *f, va_list va,
    size_t lineno)
{
        char *buf = NULL;
        
        /* Only the first error is ok */
        if (ms->event_flags & EVENT_HAD_ERR)
                return;
        if (lineno != 0) {
                efree(ms->o.buf);
                ms->o.buf = NULL;
                file_printf(ms, "line %" SIZE_T_FORMAT "u: ", lineno);
        }

        vspprintf(&buf, 0, f, va);
        va_end(va);
        
        if (error > 0) {
                file_printf(ms, "%s (%s)", (*buf ? buf : ""), strerror(error));
        } else if (*buf) {
                file_printf(ms, "%s", buf);
        }
        
        if (buf) {
                efree(buf);
        }

        ms->event_flags |= EVENT_HAD_ERR;
        ms->error = error;
}

/*VARARGS*/
protected void
file_error(struct magic_set *ms, int error, const char *f, ...)
{
        va_list va;
        va_start(va, f);
        file_error_core(ms, error, f, va, 0);
        va_end(va);
}

/*
 * Print an error with magic line number.
 */
/*VARARGS*/
protected void
file_magerror(struct magic_set *ms, const char *f, ...)
{
        va_list va;
        va_start(va, f);
        file_error_core(ms, 0, f, va, ms->line);
        va_end(va);
}

protected void
file_oomem(struct magic_set *ms, size_t len)
{
        file_error(ms, errno, "cannot allocate %" SIZE_T_FORMAT "u bytes",
            len);
}

protected void
file_badseek(struct magic_set *ms)
{
        file_error(ms, errno, "error seeking");
}

protected void
file_badread(struct magic_set *ms)
{
        file_error(ms, errno, "error reading");
}

protected int
file_buffer(struct magic_set *ms, php_stream *stream, const char *inname, const void *buf,
    size_t nb)
{
        int m = 0, rv = 0, looks_text = 0;
        int mime = ms->flags & MAGIC_MIME;
        const unsigned char *ubuf = CAST(const unsigned char *, buf);
        unichar *u8buf = NULL;
        size_t ulen;
        const char *code = NULL;
        const char *code_mime = "binary";
        const char *type = NULL;



        if (nb == 0) {
                if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
                    file_printf(ms, mime ? "application/x-empty" :
                    "empty") == -1)
                        return -1;
                return 1;
        } else if (nb == 1) {
                if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
                    file_printf(ms, mime ? "application/octet-stream" :
                    "very short file (no magic)") == -1)
                        return -1;
                return 1;
        }

        if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) {
                looks_text = file_encoding(ms, ubuf, nb, &u8buf, &ulen,
                    &code, &code_mime, &type);
        }

#ifdef __EMX__
        if ((ms->flags & MAGIC_NO_CHECK_APPTYPE) == 0 && inname) {
                switch (file_os2_apptype(ms, inname, buf, nb)) {
                case -1:
                        return -1;
                case 0:
                        break;
                default:
                        return 1;
                }
        }
#endif

#if PHP_FILEINFO_UNCOMPRESS
        if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) == 0)
                if ((m = file_zmagic(ms, stream, inname, ubuf, nb)) != 0) {
                        if ((ms->flags & MAGIC_DEBUG) != 0)
                                (void)fprintf(stderr, "zmagic %d\n", m);
                        goto done;
                }
#endif
        /* Check if we have a tar file */
        if ((ms->flags & MAGIC_NO_CHECK_TAR) == 0)
                if ((m = file_is_tar(ms, ubuf, nb)) != 0) {
                        if ((ms->flags & MAGIC_DEBUG) != 0)
                                (void)fprintf(stderr, "tar %d\n", m);
                        goto done;
                }

        /* Check if we have a CDF file */
        if ((ms->flags & MAGIC_NO_CHECK_CDF) == 0) {
                int fd;
                TSRMLS_FETCH();
                if (stream && SUCCESS == php_stream_cast(stream, PHP_STREAM_AS_FD, (void **)&fd, 0)) {
                        if ((m = file_trycdf(ms, fd, ubuf, nb)) != 0) {
                                if ((ms->flags & MAGIC_DEBUG) != 0)
                                        (void)fprintf(stderr, "cdf %d\n", m);
                                goto done;
                        }
                }
        }

        /* try soft magic tests */
        if ((ms->flags & MAGIC_NO_CHECK_SOFT) == 0)
                if ((m = file_softmagic(ms, ubuf, nb, BINTEST,
                    looks_text)) != 0) {
                        if ((ms->flags & MAGIC_DEBUG) != 0)
                                (void)fprintf(stderr, "softmagic %d\n", m);
#ifdef BUILTIN_ELF
                        if ((ms->flags & MAGIC_NO_CHECK_ELF) == 0 && m == 1 &&
                            nb > 5 && fd != -1) {
                                /*
                                 * We matched something in the file, so this
                                 * *might* be an ELF file, and the file is at
                                 * least 5 bytes long, so if it's an ELF file
                                 * it has at least one byte past the ELF magic
                                 * number - try extracting information from the
                                 * ELF headers that cannot easily * be
                                 * extracted with rules in the magic file.
                                 */
                                if ((m = file_tryelf(ms, fd, ubuf, nb)) != 0)
                                        if ((ms->flags & MAGIC_DEBUG) != 0)
                                                (void)fprintf(stderr,
                                                    "elf %d\n", m);
                        }
#endif
                        goto done;
                }

        /* try text properties */
        if ((ms->flags & MAGIC_NO_CHECK_TEXT) == 0) {

                if ((m = file_ascmagic(ms, ubuf, nb, looks_text)) != 0) {
                        if ((ms->flags & MAGIC_DEBUG) != 0)
                                (void)fprintf(stderr, "ascmagic %d\n", m);
                        goto done;
                }

                /* try to discover text encoding */
                if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) {
                        if (looks_text == 0)
                                if ((m = file_ascmagic_with_encoding( ms, ubuf,
                                    nb, u8buf, ulen, code, type, looks_text))
                                    != 0) {
                                        if ((ms->flags & MAGIC_DEBUG) != 0)
                                                (void)fprintf(stderr,
                                                    "ascmagic/enc %d\n", m);
                                        goto done;
                                }
                }
        }

        /* give up */
        m = 1;
        if ((!mime || (mime & MAGIC_MIME_TYPE)) &&
            file_printf(ms, mime ? "application/octet-stream" : "data") == -1) {
            rv = -1;
        }
 done:
        if ((ms->flags & MAGIC_MIME_ENCODING) != 0) {
                if (ms->flags & MAGIC_MIME_TYPE)
                        if (file_printf(ms, "; charset=") == -1)
                                rv = -1;
                if (file_printf(ms, "%s", code_mime) == -1)
                        rv = -1;
        }
        free(u8buf);
        if (rv)
                return rv;

        return m;
}

protected int
file_reset(struct magic_set *ms)
{
        if (ms->mlist[0] == NULL) {
                file_error(ms, 0, "no magic files loaded");
                return -1;
        }
        if (ms->o.buf) {
                efree(ms->o.buf);
                ms->o.buf = NULL;
        }
        if (ms->o.pbuf) {
                efree(ms->o.pbuf);
                ms->o.pbuf = NULL;
        }
        ms->event_flags &= ~EVENT_HAD_ERR;
        ms->error = -1;
        return 0;
}

#define OCTALIFY(n, o)  \
        /*LINTED*/ \
        (void)(*(n)++ = '\\', \
        *(n)++ = (((uint32_t)*(o) >> 6) & 3) + '0', \
        *(n)++ = (((uint32_t)*(o) >> 3) & 7) + '0', \
        *(n)++ = (((uint32_t)*(o) >> 0) & 7) + '0', \
        (o)++)

protected const char *
file_getbuffer(struct magic_set *ms)
{
        char *op, *np;
        size_t psize, len;

        if (ms->event_flags & EVENT_HAD_ERR)
                return NULL;

        if (ms->flags & MAGIC_RAW)
                return ms->o.buf;

        if (ms->o.buf == NULL)
                return NULL;

        /* * 4 is for octal representation, + 1 is for NUL */
        len = strlen(ms->o.buf);
        if (len > (SIZE_MAX - 1) / 4) {
                return NULL;
        }
        psize = len * 4 + 1;
        if ((ms->o.pbuf = CAST(char *, erealloc(ms->o.pbuf, psize))) == NULL) {
                file_oomem(ms, psize);
                return NULL;
        }

#if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
        {
                mbstate_t state;
                wchar_t nextchar;
                int mb_conv = 1;
                size_t bytesconsumed;
                char *eop;
                (void)memset(&state, 0, sizeof(mbstate_t));

                np = ms->o.pbuf;
                op = ms->o.buf;
                eop = op + len;

                while (op < eop) {
                        bytesconsumed = mbrtowc(&nextchar, op,
                            (size_t)(eop - op), &state);
                        if (bytesconsumed == (size_t)(-1) ||
                            bytesconsumed == (size_t)(-2)) {
                                mb_conv = 0;
                                break;
                        }

                        if (iswprint(nextchar)) {
                                (void)memcpy(np, op, bytesconsumed);
                                op += bytesconsumed;
                                np += bytesconsumed;
                        } else {
                                while (bytesconsumed-- > 0)
                                        OCTALIFY(np, op);
                        }
                }
                *np = '\0';

                /* Parsing succeeded as a multi-byte sequence */
                if (mb_conv != 0)
                        return ms->o.pbuf;
        }
#endif

        for (np = ms->o.pbuf, op = ms->o.buf; *op;) {
                if (isprint((unsigned char)*op)) {
                        *np++ = *op++;
                } else {
                        OCTALIFY(np, op);
                }
        }
        *np = '\0';
        return ms->o.pbuf;
}

protected int
file_check_mem(struct magic_set *ms, unsigned int level)
{
        size_t len;

        if (level >= ms->c.len) {
                len = (ms->c.len += 20) * sizeof(*ms->c.li);
                ms->c.li = CAST(struct level_info *, (ms->c.li == NULL) ?
                    emalloc(len) :
                    erealloc(ms->c.li, len));
                if (ms->c.li == NULL) {
                        file_oomem(ms, len);
                        return -1;
                }
        }
        ms->c.li[level].got_match = 0;
#ifdef ENABLE_CONDITIONALS
        ms->c.li[level].last_match = 0;
        ms->c.li[level].last_cond = COND_NONE;
#endif /* ENABLE_CONDITIONALS */
        return 0;
}

protected size_t
file_printedlen(const struct magic_set *ms)
{
        return ms->o.buf == NULL ? 0 : strlen(ms->o.buf);
}


protected int 
file_replace(struct magic_set *ms, const char *pat, const char *rep)
{
        zval *patt;
        int opts = 0;
        pcre_cache_entry *pce;
        char *res;
        zval *repl;
        int res_len, rep_cnt = 0;
        TSRMLS_FETCH();

        MAKE_STD_ZVAL(patt);
        ZVAL_STRINGL(patt, pat, strlen(pat), 0);
        opts |= PCRE_MULTILINE;
        convert_libmagic_pattern(patt, opts);
        if ((pce = pcre_get_compiled_regex_cache(Z_STRVAL_P(patt), Z_STRLEN_P(patt) TSRMLS_CC)) == NULL) {
                zval_dtor(patt);
                FREE_ZVAL(patt);
                return -1;
        }

        MAKE_STD_ZVAL(repl);
        ZVAL_STRINGL(repl, rep, strlen(rep), 0);

        res = php_pcre_replace_impl(pce, ms->o.buf, strlen(ms->o.buf), repl,
                        0, &res_len, -1, &rep_cnt TSRMLS_CC);

        FREE_ZVAL(repl);
        zval_dtor(patt);
        FREE_ZVAL(patt);

        if (NULL == res) {
                return -1;
        }

        strncpy(ms->o.buf, res, res_len);
        ms->o.buf[res_len] = '\0';

        efree(res);

        return rep_cnt;
}


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