X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=src%2Ftrackfds.h;h=f0ba8791d8485fd5441ae7bcd45109bdda482560;hb=ba2283bd3780a13f26521c5c47deedfc7184ed7d;hp=b9089bbd25b0444772c6442ca27dedd3ac7e4334;hpb=6d6ad4423ae87771bd44f90006a648ec03931961;p=coloredstderr%2Fcoloredstderr.git

diff --git a/src/trackfds.h b/src/trackfds.h
index b9089bb..f0ba879 100644
--- a/src/trackfds.h
+++ b/src/trackfds.h
@@ -100,7 +100,7 @@ static void init_from_environment(void) {
 #ifdef DEBUG
     debug("  getenv(\"%s\"): \"%s\"\n", ENV_NAME_FDS, env);
 #endif
-    /* Environment is read-only. */
+    /* Environment must be treated read-only. */
     char env_copy[strlen(env) + 1];
     strcpy(env_copy, env);
 
@@ -124,18 +124,21 @@ static void init_from_environment(void) {
         }
         /* ',' at the beginning or double ',' - ignore. */
         if (x == last) {
-            last = x + 1;
-            continue;
+            goto next;
         }
 
         if (i == count) {
             break;
         }
 
+        /* Replace ',' to null-terminate number for atoi(). */
         *x = 0;
 
         int fd = atoi(last);
-        if (fd < TRACKFDS_STATIC_COUNT) {
+        if (fd < 0) {
+            goto next;
+
+        } else if (fd < TRACKFDS_STATIC_COUNT) {
             tracked_fds[fd] = 1;
         } else {
             if (!tracked_fds_list) {
@@ -169,7 +172,7 @@ static char *update_environment_buffer_entry(char *x, int fd) {
     assert(fd >= 0);
 
     int length = snprintf(x, 10 + 1, "%d", fd);
-    if (length >= 10 + 1) {
+    if (length >= 10 + 1 || length <= 0 /* shouldn't happen */) {
         /* Integer too big to fit the buffer, skip it. */
 #ifdef WARNING
         warning("update_environment_buffer_entry(): truncated fd: %d [%d]\n",
@@ -181,7 +184,7 @@ static char *update_environment_buffer_entry(char *x, int fd) {
     /* Write comma after number. */
     x += length;
     *x++ = ',';
-    /* Make sure the string is always zero terminated. */
+    /* Make sure the string is always null-terminated. */
     *x = 0;
 
     return x;
@@ -325,8 +328,12 @@ static int tracked_fds_find_slow(int fd) noinline;
  * they are not called often enough.
  */
 inline static int tracked_fds_find(int fd) always_inline;
-static int tracked_fds_find(int fd) {
-    assert(fd >= 0);
+inline static int tracked_fds_find(int fd) {
+    /* Invalid file descriptor. No assert() as we're called from the hooked
+     * macro. */
+    if (unlikely(fd < 0)) {
+        return 0;
+    }
 
     if (fd < TRACKFDS_STATIC_COUNT) {
         return tracked_fds[fd];
@@ -336,6 +343,7 @@ static int tracked_fds_find(int fd) {
 }
 static int tracked_fds_find_slow(int fd) {
     assert(initialized);
+    assert(fd >= 0);
 
     if (tracked_fds_list_count == 0) {
         return 0;