123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264 |
- /*
- * 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"
- #include "magic.h"
- #include <stdarg.h>
- #include <stdlib.h>
- #include <string.h>
- #include <ctype.h>
- #if defined(HAVE_WCHAR_H)
- #include <wchar.h>
- #endif
- #ifndef lint
- FILE_RCSID("@(#)$Id: funcs.c,v 1.19 2006/03/02 22:10:26 christos Exp $")
- #endif /* lint */
- #ifndef HAVE_VSNPRINTF
- int vsnprintf(char *, size_t, const char *, va_list);
- #endif
- /*
- * Like printf, only we print to a buffer and advance it.
- */
- protected int
- file_printf(struct magic_set *ms, const char *fmt, ...)
- {
- va_list ap;
- size_t len;
- char *buf;
- va_start(ap, fmt);
- if ((len = vsnprintf(ms->o.ptr, ms->o.len, fmt, ap)) >= ms->o.len) {
- va_end(ap);
- if ((buf = realloc(ms->o.buf, len + 1024)) == NULL) {
- file_oomem(ms);
- return -1;
- }
- ms->o.ptr = buf + (ms->o.ptr - ms->o.buf);
- ms->o.buf = buf;
- ms->o.len = ms->o.size - (ms->o.ptr - ms->o.buf);
- ms->o.size = len + 1024;
- va_start(ap, fmt);
- len = vsnprintf(ms->o.ptr, ms->o.len, fmt, ap);
- }
- ms->o.ptr += len;
- ms->o.len -= len;
- va_end(ap);
- return 0;
- }
- /*
- * error - print best error message possible
- */
- /*VARARGS*/
- protected void
- file_error(struct magic_set *ms, int error, const char *f, ...)
- {
- va_list va;
- /* Only the first error is ok */
- if (ms->haderr)
- return;
- va_start(va, f);
- (void)vsnprintf(ms->o.buf, ms->o.size, f, va);
- va_end(va);
- if (error > 0) {
- size_t len = strlen(ms->o.buf);
- (void)snprintf(ms->o.buf + len, ms->o.size - len, " (%s)",
- strerror(error));
- }
- ms->haderr++;
- ms->error = error;
- }
- protected void
- file_oomem(struct magic_set *ms)
- {
- file_error(ms, errno, "cannot allocate memory");
- }
- 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 void *buf, size_t nb)
- {
- int m;
- /* try compression stuff */
- if ((m = file_zmagic(ms, fd, buf, nb)) == 0) {
- /* Check if we have a tar file */
- if ((m = file_is_tar(ms, buf, nb)) == 0) {
- /* try tests in /etc/magic (or surrogate magic file) */
- if ((m = file_softmagic(ms, buf, nb)) == 0) {
- /* try known keywords, check whether it is ASCII */
- if ((m = file_ascmagic(ms, buf, nb)) == 0) {
- /* abandon hope, all ye who remain here */
- if (file_printf(ms, ms->flags & MAGIC_MIME ?
- (nb ? "application/octet-stream" :
- "application/empty") :
- (nb ? "data" :
- "empty")) == -1)
- return -1;
- m = 1;
- }
- }
- }
- }
- 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;
- }
- ms->o.ptr = ms->o.buf;
- ms->haderr = 0;
- ms->error = -1;
- return 0;
- }
- #define OCTALIFY(n, o) \
- *(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 *nbuf, *op, *np;
- size_t nsize;
- if (ms->haderr)
- return NULL;
- if (ms->flags & MAGIC_RAW)
- return ms->o.buf;
- nsize = ms->o.len * 4 + 1;
- if (ms->o.psize < nsize) {
- if ((nbuf = realloc(ms->o.pbuf, nsize)) == NULL) {
- file_oomem(ms);
- return NULL;
- }
- ms->o.psize = nsize;
- ms->o.pbuf = nbuf;
- }
- #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 + strlen(ms->o.buf);
- while (op < eop) {
- bytesconsumed = mbrtowc(&nextchar, op, 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; op++) {
- if (isprint((unsigned char)*op)) {
- *np++ = *op;
- } else {
- OCTALIFY(np, op);
- }
- }
- *np = '\0';
- return ms->o.pbuf;
- }
- /*
- * Yes these suffer from buffer overflows, but if your OS does not have
- * these functions, then maybe you should consider replacing your OS?
- */
- #ifndef HAVE_VSNPRINTF
- int
- vsnprintf(char *buf, size_t len, const char *fmt, va_list ap)
- {
- return vsprintf(buf, fmt, ap);
- }
- #endif
- #ifndef HAVE_SNPRINTF
- /*ARGSUSED*/
- int
- snprintf(char *buf, size_t len, const char *fmt, ...)
- {
- int rv;
- va_list ap;
- va_start(ap, fmt);
- rv = vsprintf(buf, fmt, ap);
- va_end(ap);
- return rv;
- }
- #endif
|