diff options
-rw-r--r-- | libexec/rtld-elf/rtld.c | 148 |
1 files changed, 75 insertions, 73 deletions
diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c index bb790dd..7a3938f 100644 --- a/libexec/rtld-elf/rtld.c +++ b/libexec/rtld-elf/rtld.c @@ -145,9 +145,8 @@ static void unlink_object(Obj_Entry *); static void unload_object(Obj_Entry *); static void unref_dag(Obj_Entry *); static void ref_dag(Obj_Entry *); -static int origin_subst_one(char **, const char *, const char *, - const char *, char *); -static char *origin_subst(const char *, const char *); +static char *origin_subst_one(char *, const char *, const char *, bool); +static char *origin_subst(char *, const char *); static void preinit_main(void); static int rtld_verify_versions(const Objlist *); static int rtld_verify_object_versions(Obj_Entry *); @@ -748,79 +747,80 @@ basename(const char *name) static struct utsname uts; -static int -origin_subst_one(char **res, const char *real, const char *kw, const char *subst, - char *may_free) +static char * +origin_subst_one(char *real, const char *kw, const char *subst, + bool may_free) { - const char *p, *p1; - char *res1; - int subst_len; - int kw_len; - - res1 = *res = NULL; - p = real; - subst_len = kw_len = 0; - for (;;) { - p1 = strstr(p, kw); - if (p1 != NULL) { - if (subst_len == 0) { - subst_len = strlen(subst); - kw_len = strlen(kw); - } - if (*res == NULL) { - *res = xmalloc(PATH_MAX); - res1 = *res; - } - if ((res1 - *res) + subst_len + (p1 - p) >= PATH_MAX) { - _rtld_error("Substitution of %s in %s cannot be performed", - kw, real); - if (may_free != NULL) - free(may_free); - free(res); - return (false); - } - memcpy(res1, p, p1 - p); - res1 += p1 - p; - memcpy(res1, subst, subst_len); - res1 += subst_len; - p = p1 + kw_len; - } else { - if (*res == NULL) { - if (may_free != NULL) - *res = may_free; - else - *res = xstrdup(real); - return (true); - } - *res1 = '\0'; - if (may_free != NULL) - free(may_free); - if (strlcat(res1, p, PATH_MAX - (res1 - *res)) >= PATH_MAX) { - free(res); - return (false); - } - return (true); - } - } + char *p, *p1, *res, *resp; + int subst_len, kw_len, subst_count, old_len, new_len; + + kw_len = strlen(kw); + + /* + * First, count the number of the keyword occurences, to + * preallocate the final string. + */ + for (p = real, subst_count = 0;; p = p1 + kw_len, subst_count++) { + p1 = strstr(p, kw); + if (p1 == NULL) + break; + } + + /* + * If the keyword is not found, just return. + */ + if (subst_count == 0) + return (may_free ? real : xstrdup(real)); + + /* + * There is indeed something to substitute. Calculate the + * length of the resulting string, and allocate it. + */ + subst_len = strlen(subst); + old_len = strlen(real); + new_len = old_len + (subst_len - kw_len) * subst_count; + res = xmalloc(new_len + 1); + + /* + * Now, execute the substitution loop. + */ + for (p = real, resp = res;;) { + p1 = strstr(p, kw); + if (p1 != NULL) { + /* Copy the prefix before keyword. */ + memcpy(resp, p, p1 - p); + resp += p1 - p; + /* Keyword replacement. */ + memcpy(resp, subst, subst_len); + resp += subst_len; + p = p1 + kw_len; + } else + break; + } + + /* Copy to the end of string and finish. */ + strcat(resp, p); + if (may_free) + free(real); + return (res); } static char * -origin_subst(const char *real, const char *origin_path) +origin_subst(char *real, const char *origin_path) { - char *res1, *res2, *res3, *res4; + char *res1, *res2, *res3, *res4; - if (uts.sysname[0] == '\0') { - if (uname(&uts) != 0) { - _rtld_error("utsname failed: %d", errno); - return (NULL); + if (uts.sysname[0] == '\0') { + if (uname(&uts) != 0) { + _rtld_error("utsname failed: %d", errno); + return (NULL); + } } - } - if (!origin_subst_one(&res1, real, "$ORIGIN", origin_path, NULL) || - !origin_subst_one(&res2, res1, "$OSNAME", uts.sysname, res1) || - !origin_subst_one(&res3, res2, "$OSREL", uts.release, res2) || - !origin_subst_one(&res4, res3, "$PLATFORM", uts.machine, res3)) - return (NULL); - return (res4); + res1 = origin_subst_one(real, "$ORIGIN", origin_path, false); + res2 = origin_subst_one(res1, "$OSNAME", uts.sysname, true); + res3 = origin_subst_one(res2, "$OSREL", uts.release, true); + res4 = origin_subst_one(res3, "$PLATFORM", uts.machine, true); + return (res4); } static void @@ -1438,10 +1438,12 @@ find_library(const char *xname, const Obj_Entry *refobj) xname); return NULL; } - if (objgiven && refobj->z_origin) - return origin_subst(xname, refobj->origin_path); - else - return xstrdup(xname); + if (objgiven && refobj->z_origin) { + return (origin_subst(__DECONST(char *, xname), + refobj->origin_path)); + } else { + return (xstrdup(xname)); + } } if (libmap_disable || !objgiven || |