Don't abuse the const pointer we've been passed in, allocate memory instead.

XXX: This is expensive.

diff --git a/src/softmagic.c b/src/softmagic.c
index 0c60e80f5dd2805f0fc52c25143f406f9212b539..bcbee4e5c0801b543a8935edae68aa528c1de156 100644 (file)
--- a/src/softmagic.c
+++ b/src/softmagic.c
@@ -32,7 +32,7 @@
 #include "file.h"
 
 #ifndef        lint
-FILE_RCSID("@(#)$File: softmagic.c,v 1.193 2014/09/10 18:41:51 christos Exp $")
+FILE_RCSID("@(#)$File: softmagic.c,v 1.194 2014/09/22 18:26:19 christos Exp $")
 #endif /* lint */
 
 #include "magic.h"
@@ -74,6 +74,7 @@ file_softmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes,
 {
        struct mlist *ml;
        int rv, printed_something = 0, need_separator = 0;
+
        for (ml = ms->mlist[0]->next; ml != ms->mlist[0]; ml = ml->next)
                if ((rv = match(ms, ml->magic, ml->nmagic, buf, nbytes, 0, mode,
                    text, 0, level, &printed_something, &need_separator,
@@ -1940,6 +1941,7 @@ magiccheck(struct magic_set *ms, struct magic *m)
        case FILE_REGEX: {
                int rc;
                file_regex_t rx;
+               const char *search;
 
                if (ms->search.s == NULL)
                        return 0;
@@ -1956,19 +1958,30 @@ magiccheck(struct magic_set *ms, struct magic *m)
                        size_t slen = ms->search.s_len;
 #ifndef REG_STARTEND
 #define        REG_STARTEND    0
-                       char c;
-                       if (slen != 0)
-                               slen--;
-                       c = ms->search.s[slen];
-                       ((char *)(intptr_t)ms->search.s)[slen] = '\0';
+                       char *copy;
+                       if (slen != 0) {
+                           copy = malloc(slen);
+                           if (copy == NULL)  {
+                               file_error(ms, errno,
+                                   "can't allocate %zu bytes", slen);
+                               return -1;
+                           }
+                           memcpy(copy, ms->search.s, slen);
+                           copy[--slen] = '\0';
+                           search = copy;
+                       } else {
+                           search = ms->search.s;
+                           copy = NULL;
+                       }
 #else
+                       search = ms->search.s;
                        pmatch[0].rm_so = 0;
                        pmatch[0].rm_eo = slen;
 #endif
-                       rc = file_regexec(&rx, (const char *)ms->search.s,
+                       rc = file_regexec(&rx, (const char *)search,
                            1, pmatch, REG_STARTEND);
 #if REG_STARTEND == 0
-                       ((char *)(intptr_t)ms->search.s)[l] = c;
+                       free(copy);
 #endif
                        switch (rc) {
                        case 0: