X-Git-Url: https://ruderich.org/simon/gitweb/?p=coloredstderr%2Fcoloredstderr.git;a=blobdiff_plain;f=src%2Ftrackfds.h;h=b9089bbd25b0444772c6442ca27dedd3ac7e4334;hp=8237781580d4e32266d11dccce3c7139c4866e97;hb=6d6ad4423ae87771bd44f90006a648ec03931961;hpb=7691b7aa1a84b8bc0f911fd869221679e2ff0c95

diff --git a/src/trackfds.h b/src/trackfds.h
index 8237781..b9089bb 100644
--- a/src/trackfds.h
+++ b/src/trackfds.h
@@ -51,12 +51,14 @@ static void tracked_fds_debug(void) {
 #endif
 
 static int init_tracked_fds_list(size_t count) {
+    assert(count > 0);
+
     /* Reduce reallocs. */
     count += TRACKFDS_REALLOC_STEP;
 
     tracked_fds_list = malloc(count * sizeof(*tracked_fds_list));
     if (!tracked_fds_list) {
-#ifdef DEBUG
+#ifdef WARNING
         warning("malloc(tracked_fds_list, %d) failed [%d]\n",
                 count * sizeof(*tracked_fds_list), getpid());
 #endif
@@ -78,6 +80,8 @@ static void init_from_environment(void) {
 #endif
     char const *env;
 
+    int saved_errno = errno;
+
     initialized = 1;
     tracked_fds_list_count = 0;
 
@@ -90,8 +94,12 @@ static void init_from_environment(void) {
 
     env = getenv(ENV_NAME_FDS);
     if (!env) {
+        errno = saved_errno;
         return;
     }
+#ifdef DEBUG
+    debug("  getenv(\"%s\"): \"%s\"\n", ENV_NAME_FDS, env);
+#endif
     /* Environment is read-only. */
     char env_copy[strlen(env) + 1];
     strcpy(env_copy, env);
@@ -153,13 +161,17 @@ next:
 #ifdef DEBUG
     tracked_fds_debug();
 #endif
+
+    errno = saved_errno;
 }
 
 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) {
         /* Integer too big to fit the buffer, skip it. */
-#ifdef DEBUG
+#ifdef WARNING
         warning("update_environment_buffer_entry(): truncated fd: %d [%d]\n",
                 fd, getpid());
 #endif
@@ -175,6 +187,8 @@ static char *update_environment_buffer_entry(char *x, int fd) {
     return x;
 }
 static void update_environment_buffer(char *x) {
+    assert(initialized);
+
     size_t i;
     for (i = 0; i < TRACKFDS_STATIC_COUNT; i++) {
         if (tracked_fds[i]) {
@@ -186,6 +200,8 @@ static void update_environment_buffer(char *x) {
     }
 }
 inline static size_t update_environment_buffer_size(void) {
+    assert(initialized);
+
     /* Use the maximum count (TRACKFDS_STATIC_COUNT) of used descriptors
      * because it's simple and small enough not to be a problem.
      *
@@ -212,7 +228,7 @@ static void update_environment(void) {
     update_environment_buffer(env);
 
 #if 0
-    debug("    setenv('%s', '%s', 1)\n", ENV_NAME_FDS, env);
+    debug("    setenv(\"%s\", \"%s\", 1)\n", ENV_NAME_FDS, env);
 #endif
 
     setenv(ENV_NAME_FDS, env, 1 /* overwrite */);
@@ -221,6 +237,8 @@ static void update_environment(void) {
 
 
 static void tracked_fds_add(int fd) {
+    assert(fd >= 0);
+
     if (fd < TRACKFDS_STATIC_COUNT) {
         tracked_fds[fd] = 1;
 #if 0
@@ -231,6 +249,8 @@ static void tracked_fds_add(int fd) {
     }
 
     if (tracked_fds_list_count >= tracked_fds_list_space) {
+        int saved_errno = errno;
+
         size_t new_space = tracked_fds_list_space + TRACKFDS_REALLOC_STEP;
         int *tmp = realloc(tracked_fds_list,
                            sizeof(*tracked_fds_list) * new_space);
@@ -238,12 +258,15 @@ static void tracked_fds_add(int fd) {
             /* We can do nothing, just ignore the error. We made sure not to
              * destroy our state, so the new descriptor is ignored without any
              * other consequences. */
-#ifdef DEBUG
+#ifdef WARNING
             warning("realloc(tracked_fds_list, %zu) failed! [%d]\n",
                     sizeof(*tracked_fds_list) * new_space, getpid());
 #endif
+            errno = saved_errno;
             return;
         }
+        errno = saved_errno;
+
         tracked_fds_list = tmp;
         tracked_fds_list_space = new_space;
     }
@@ -256,6 +279,8 @@ static void tracked_fds_add(int fd) {
 #endif
 }
 static int tracked_fds_remove(int fd) {
+    assert(fd >= 0);
+
     if (fd < TRACKFDS_STATIC_COUNT) {
         int old_value = tracked_fds[fd];
         tracked_fds[fd] = 0;
@@ -289,10 +314,29 @@ static int tracked_fds_remove(int fd) {
     /* Not found. */
     return 0;
 }
+
+static int tracked_fds_find_slow(int fd) noinline;
+/*
+ * tracked_fds_find() is called for each hook call and should be as fast as
+ * possible. As most file descriptors are < TRACKFDS_STATIC_COUNT, force the
+ * compiler to inline that part which is almost exclusively used.
+ *
+ * Inlining tracked_fds_add()/tracked_fds_remove() isn't worth the effort as
+ * 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);
+
     if (fd < TRACKFDS_STATIC_COUNT) {
         return tracked_fds[fd];
     }
+
+    return tracked_fds_find_slow(fd);
+}
+static int tracked_fds_find_slow(int fd) {
+    assert(initialized);
+
     if (tracked_fds_list_count == 0) {
         return 0;
     }