freebsd-dev/contrib/file/funcs.c
2012-04-19 03:20:13 +00:00

462 lines
11 KiB
C

/*
* 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 1.60 2011/12/08 12:38:24 rrt 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
#if defined(HAVE_LIMITS_H)
#include <limits.h>
#endif
#ifndef SIZE_MAX
#define SIZE_MAX ((size_t)~0)
#endif
/*
* Like printf, only we append to a buffer.
*/
protected int
file_vprintf(struct magic_set *ms, const char *fmt, va_list ap)
{
int len;
char *buf, *newstr;
len = vasprintf(&buf, fmt, ap);
if (len < 0)
goto out;
if (ms->o.buf != NULL) {
len = asprintf(&newstr, "%s%s", ms->o.buf, buf);
free(buf);
if (len < 0)
goto out;
free(ms->o.buf);
buf = newstr;
}
ms->o.buf = buf;
return 0;
out:
file_error(ms, errno, "vasprintf failed");
return -1;
}
protected int
file_printf(struct magic_set *ms, const char *fmt, ...)
{
int rv;
va_list ap;
va_start(ap, fmt);
rv = file_vprintf(ms, fmt, ap);
va_end(ap);
return rv;
}
/*
* 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)
{
/* Only the first error is ok */
if (ms->event_flags & EVENT_HAD_ERR)
return;
if (lineno != 0) {
free(ms->o.buf);
ms->o.buf = NULL;
file_printf(ms, "line %" SIZE_T_FORMAT "u: ", lineno);
}
file_vprintf(ms, f, va);
if (error > 0)
file_printf(ms, " (%s)", strerror(error));
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");
}
#ifndef COMPILE_ONLY
protected int
file_buffer(struct magic_set *ms, int fd, const char *inname __attribute__ ((unused)),
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 HAVE_FORK
/* try compression stuff */
if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) == 0)
if ((m = file_zmagic(ms, fd, 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)
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;
}
#endif
protected int
file_reset(struct magic_set *ms)
{
if (ms->mlist == NULL) {
file_error(ms, 0, "no magic files loaded");
return -1;
}
if (ms->o.buf) {
free(ms->o.buf);
ms->o.buf = NULL;
}
if (ms->o.pbuf) {
free(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 *pbuf, *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) {
file_oomem(ms, len);
return NULL;
}
psize = len * 4 + 1;
if ((pbuf = CAST(char *, realloc(ms->o.pbuf, psize))) == NULL) {
file_oomem(ms, psize);
return NULL;
}
ms->o.pbuf = pbuf;
#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) ?
malloc(len) :
realloc(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)
{
regex_t rx;
int rc;
rc = regcomp(&rx, pat, REG_EXTENDED);
if (rc) {
char errmsg[512];
(void)regerror(rc, &rx, errmsg, sizeof(errmsg));
file_magerror(ms, "regex error %d, (%s)", rc, errmsg);
return -1;
} else {
regmatch_t rm;
int nm = 0;
while (regexec(&rx, ms->o.buf, 1, &rm, 0) == 0) {
ms->o.buf[rm.rm_so] = '\0';
if (file_printf(ms, "%s%s", rep,
rm.rm_eo != 0 ? ms->o.buf + rm.rm_eo : "") == -1)
return -1;
nm++;
}
regfree(&rx);
return nm;
}
}