ilimination of system code, removal of x-watcher and replacement of it by dmon, fixes in audio code, dynamic asset reload

third-party/dmon/dmon_extra.h

@@ -0,0 +1,164 @@
+#ifndef __DMON_EXTRA_H__
+#define __DMON_EXTRA_H__
+
+//
+// Copyright 2023 Sepehr Taghdisian (septag@github). All rights reserved.
+// License: https://github.com/septag/dmon#license-bsd-2-clause
+//
+//  Extra header functionality for dmon.h for the backend based on inotify
+//  
+//  Add/Remove directory functions:
+//  dmon_watch_add: Adds a sub-directory to already valid watch_id. sub-directories are assumed to be relative to watch root_dir
+//  dmon_watch_add: Removes a sub-directory from already valid watch_id. sub-directories are assumed to be relative to watch root_dir
+//  Reason: The inotify backend does not work well when watching in recursive mode a root directory of a large tree, it may take
+//          quite a while until all inotify watches are established, and events will not be received in this time.  Also, since one
+//          inotify watch will be established per subdirectory, it is possible that the maximum amount of inotify watches per user
+//          will be reached. The default maximum is 8192.
+//          When using inotify backend users may turn off the DMON_WATCHFLAGS_RECURSIVE flag and add/remove selectively the
+//          sub-directories to be watched based on application-specific logic about which sub-directory actually needs to be watched.
+//          The function dmon_watch_add and dmon_watch_rm are used to this purpose.
+//
+
+#ifndef __DMON_H__
+#error "Include 'dmon.h' before including this file"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+DMON_API_DECL bool dmon_watch_add(dmon_watch_id id, const char* subdir);
+DMON_API_DECL bool dmon_watch_rm(dmon_watch_id id, const char* watchdir);
+
+#ifdef __cplusplus
+}
+#endif
+
+#ifdef DMON_IMPL
+#if DMON_OS_LINUX
+DMON_API_IMPL bool dmon_watch_add(dmon_watch_id id, const char* watchdir)
+{
+    DMON_ASSERT(id.id > 0 && id.id <= DMON_MAX_WATCHES);
+
+    bool skip_lock = pthread_self() == _dmon.thread_handle;
+
+    if (!skip_lock)
+        pthread_mutex_lock(&_dmon.mutex);
+
+    dmon__watch_state* watch = _dmon.watches[id.id - 1];
+
+    int dirlen, i, c;
+
+    // check if the directory exists
+    // if watchdir contains absolute/root-included path, try to strip the rootdir from it
+    // else, we assume that watchdir is correct, so save it as it is
+    struct stat st;
+    dmon__watch_subdir subdir;
+    if (stat(watchdir, &st) == 0 && (st.st_mode & S_IFDIR)) {
+        _dmon_strcpy(subdir.rootdir, sizeof(subdir.rootdir), watchdir);
+        if (strstr(subdir.rootdir, watch->rootdir) == subdir.rootdir) {
+            _dmon_strcpy(subdir.rootdir, sizeof(subdir.rootdir), watchdir + strlen(watch->rootdir));
+        }
+    } else {
+        char fullpath[DMON_MAX_PATH];
+        _dmon_strcpy(fullpath, sizeof(fullpath), watch->rootdir);
+        _dmon_strcat(fullpath, sizeof(fullpath), watchdir);
+        if (stat(fullpath, &st) != 0 || (st.st_mode & S_IFDIR) == 0) {
+            _DMON_LOG_ERRORF("Watch directory '%s' is not valid", watchdir);
+            if (!skip_lock)
+                pthread_mutex_unlock(&_dmon.mutex);
+            return false;
+        }
+        _dmon_strcpy(subdir.rootdir, sizeof(subdir.rootdir), watchdir);
+    }
+
+    dirlen = (int)strlen(subdir.rootdir);
+    if (subdir.rootdir[dirlen - 1] != '/') {
+        subdir.rootdir[dirlen] = '/';
+        subdir.rootdir[dirlen + 1] = '\0';
+    }
+
+    // check that the directory is not already added
+    for (i = 0, c = stb_sb_count(watch->subdirs); i < c; i++) {
+        if (strcmp(subdir.rootdir, watch->subdirs[i].rootdir) == 0) {
+            _DMON_LOG_ERRORF("Error watching directory '%s', because it is already added.", watchdir);
+            if (!skip_lock) 
+                pthread_mutex_unlock(&_dmon.mutex);
+            return false;
+        }
+    }
+
+    const uint32_t inotify_mask = IN_MOVED_TO | IN_CREATE | IN_MOVED_FROM | IN_DELETE | IN_MODIFY;
+    char fullpath[DMON_MAX_PATH];
+    _dmon_strcpy(fullpath, sizeof(fullpath), watch->rootdir);
+    _dmon_strcat(fullpath, sizeof(fullpath), subdir.rootdir);
+    int wd = inotify_add_watch(watch->fd, fullpath, inotify_mask);
+    if (wd == -1) {
+        _DMON_LOG_ERRORF("Error watching directory '%s'. (inotify_add_watch:err=%d)", watchdir, errno);
+        if (!skip_lock)
+            pthread_mutex_unlock(&_dmon.mutex);
+        return false;
+    }
+
+    stb_sb_push(watch->subdirs, subdir);
+    stb_sb_push(watch->wds, wd);
+
+    if (!skip_lock)
+        pthread_mutex_unlock(&_dmon.mutex);
+
+    return true;
+}
+
+DMON_API_IMPL bool dmon_watch_rm(dmon_watch_id id, const char* watchdir)
+{
+    DMON_ASSERT(id.id > 0 && id.id <= DMON_MAX_WATCHES);
+
+    bool skip_lock = pthread_self() == _dmon.thread_handle;
+
+    if (!skip_lock)
+        pthread_mutex_lock(&_dmon.mutex);
+
+    dmon__watch_state* watch = _dmon.watches[id.id - 1];
+
+    char subdir[DMON_MAX_PATH];
+    _dmon_strcpy(subdir, sizeof(subdir), watchdir);
+    if (strstr(subdir, watch->rootdir) == subdir) {
+        _dmon_strcpy(subdir, sizeof(subdir), watchdir + strlen(watch->rootdir));
+    }
+
+    int dirlen = (int)strlen(subdir);
+    if (subdir[dirlen - 1] != '/') {
+        subdir[dirlen] = '/';
+        subdir[dirlen + 1] = '\0';
+    }
+
+    int i, c = stb_sb_count(watch->subdirs);
+    for (i = 0; i < c; i++) {
+        if (strcmp(watch->subdirs[i].rootdir, subdir) == 0) {
+            break;
+        }
+    }
+    if (i >= c) {
+        _DMON_LOG_ERRORF("Watch directory '%s' is not valid", watchdir);
+        if (!skip_lock)
+            pthread_mutex_unlock(&_dmon.mutex);
+        return false;
+    }
+    inotify_rm_watch(watch->fd, watch->wds[i]);
+
+    /* Remove entry from subdirs and wds by swapping position with the last entry */
+    watch->subdirs[i] = stb_sb_last(watch->subdirs);
+    stb_sb_pop(watch->subdirs);
+
+    watch->wds[i] = stb_sb_last(watch->wds);
+    stb_sb_pop(watch->wds);
+
+    if (!skip_lock)
+        pthread_mutex_unlock(&_dmon.mutex);
+    return true;
+}
+#endif  // DMON_OS_LINUX
+#endif // DMON_IMPL
+
+#endif // __DMON_EXTRA_H__
+