make filewatcher more robust

CMakeLists.txt

@@ -47,6 +47,7 @@ add_library(hiload SHARED
   src/memory.c
   src/string/string.c
   src/filewatcher/filewatcher.c
+  src/filewatcher/filewatch.c
 
 # dependencies
   src/logger/sc_log.c

include/hiload/hiload.h

@@ -29,7 +29,7 @@ void hi_deinit(void);
 /**
  * Print a random assortment of information from current state
  */
-void hi_print_module_infos(void);
+void hi_print_loaded_modules(void);
 
 /**
  * Reload shared library if it has changed since last reload or init was called

src/common.h

@@ -1,13 +1,11 @@
 #ifndef COMMON_H_
 #define COMMON_H_
 
+#include "logger/logger.h"
 #include "types.h"
 
-static inline
-u32 has_mask(u32 flags, u32 mask) {
-    return flags & mask;
-}
+static inline u32 has_mask(u32 flags, u32 mask) { return flags & mask; }
 
-#define ARRLEN(A) (sizeof((A))/(sizeof ((A)[0])))
+#define ARRLEN(A) (sizeof((A)) / (sizeof((A)[0])))
 
 #endif // COMMON_H_

src/filewatcher/fileevent.h

@@ -1,6 +0,0 @@
-#ifndef FILEEVENT_H_
-#define FILEEVENT_H_
-
-
-
-#endif // FILEEVENT_H_

src/filewatcher/filewatch.c

@@ -0,0 +1,193 @@
+#include "filewatch.h"
+
+#include "common.h"
+#include "filewatch_context.h"
+#include "filewatch_type.h"
+
+#include <errno.h>
+#include <string.h>
+#include <sys/inotify.h>
+#include <unistd.h>
+
+/*
+ * File Watch
+ */
+
+struct WatchMaskParams {
+  u32 file_mask;
+  u32 parent_mask;
+};
+
+static inline struct WatchMaskParams inode_watch_masks_create(u32 flags) {
+
+  u32 file_mask = 0u;
+  u32 parent_mask = 0u;
+
+  if (has_mask(flags, HI_FILE_MODIFY)) {
+    file_mask |= IN_MODIFY;
+  }
+  if (has_mask(flags, HI_FILE_CREATE)) {
+    parent_mask |= IN_CREATE;
+  }
+  if (has_mask(flags, HI_FILE_DELETE)) {
+    file_mask |= IN_DELETE_SELF;
+    parent_mask |= IN_DELETE;
+  }
+  if (has_mask(flags, HI_FILE_MOVE)) {
+    file_mask |= IN_MOVE_SELF;
+    parent_mask |= IN_MOVED_TO;
+  }
+
+  // Append if watch exists
+  file_mask |= IN_MASK_ADD;
+  parent_mask |= IN_MASK_ADD;
+
+  return (struct WatchMaskParams){.file_mask = file_mask,
+                                  .parent_mask = parent_mask};
+}
+
+static void file_watch_destroy(int fd, hiFileWatch *fw) {
+  inotify_rm_watch(fd, fw->wd);
+  free((void *)fw->path);
+
+  fw->wd = -1;
+  fw->path = NULL;
+}
+
+void file_watch_destroy_watches(struct hiFileWatcherContext *ctx) {
+  for (size_t i = 0; i < sc_array_size(&ctx->watches); i++) {
+    hiFileWatch *fw = &sc_array_at(&ctx->watches, i);
+    file_watch_destroy(ctx->fd, fw);
+  }
+  sc_array_term(&ctx->watches);
+}
+
+hiFileWatch *file_watch_find_by_wd(struct hiFileWatcherContext *ctx, int wd,
+                                   size_t *index) {
+  struct sc_array_fwatch *watches = &ctx->watches;
+
+  for (size_t i = 0; i < sc_array_size(watches); ++i) {
+    hiFileWatch *fw = &sc_array_at(watches, i);
+    if (fw->wd == wd) {
+      if (index) {
+        *index = i;
+      }
+      return fw;
+    }
+  }
+  return NULL;
+}
+
+hiFileWatch *file_watch_find_by_path(struct hiFileWatcherContext *ctx,
+                                     const char *path, size_t *index) {
+  for (size_t i = 0; i < sc_array_size(&ctx->watches); i++) {
+    hiFileWatch *watch = &sc_array_at(&ctx->watches, i);
+    if (strcmp(watch->path, path) == 0) {
+      if (index) {
+        *index = i;
+      }
+      return watch;
+    }
+  }
+  return NULL;
+}
+
+/**
+ * Return null terminated char array with the parent, or NULL if no path
+ * separator was found.
+ * */
+static char *get_parent_folder(const char path[static 1]) {
+  const char *last_separator = strrchr(path, '/');
+  if (!last_separator)
+    return NULL;
+
+  size_t length = last_separator - path;
+  char *parent = calloc(length, sizeof(char));
+  strncpy(parent, path, length);
+  parent[length] = '\0';
+  return parent;
+}
+
+HiloadResult file_watch_add(hiFileWatcherContext *ctx, u32 mask,
+                            const char *path) {
+  if (!ctx || ctx->fd == -1) {
+    sc_log_error("Invalid inotify context\n");
+    return HILOAD_FAIL;
+  }
+  struct WatchMaskParams params = inode_watch_masks_create(mask);
+
+  hiFileWatch *watch = file_watch_find_by_path(ctx, path, NULL);
+  if (!watch) {
+    int wd = inotify_add_watch(ctx->fd, path, params.file_mask);
+    if (wd == -1) {
+      sc_log_error("Couldn't watch: %s: %s\n", path, strerror(errno));
+      return HILOAD_FAIL;
+    }
+    hiFileWatch wp = {.wd = wd, .mask = mask, .path = strdup(path)};
+    sc_array_add(&ctx->watches, wp);
+    watch = &sc_array_last(&ctx->watches);
+  } else {
+    inotify_add_watch(ctx->fd, path, params.file_mask);
+  }
+
+  if (!has_mask(HI_FILE_PARENT, mask)) {
+    char *parent = get_parent_folder(path);
+    hiFileWatch *parent_watch = file_watch_find_by_path(ctx, parent, NULL);
+    if (!parent_watch) {
+      // parent not yet watched
+      int wd = inotify_add_watch(ctx->fd, parent, params.parent_mask);
+      hiFileWatch wp = {.wd = wd, .mask = HI_FILE_PARENT, .path = parent};
+      sc_array_init(&wp.files);
+      sc_array_add(&wp.files, strdup(watch->path));
+      sc_array_add(&ctx->watches, wp);
+    } else {
+      free(parent);
+      inotify_add_watch(ctx->fd, parent_watch->path, params.parent_mask);
+      {
+        // Make sure we don't add a duplicate if the file is already marked
+        bool exists = false;
+        for (size_t i = 0; i < sc_array_size(&parent_watch->files); i++) {
+          const char *file = sc_array_at(&parent_watch->files, i);
+          // we store the pointer, so this should be fine
+          if (file == watch->path) {
+            exists = true;
+            break;
+          }
+        }
+        if (!exists) {
+          sc_array_add(&parent_watch->files, watch->path);
+        }
+      }
+    }
+  }
+
+  return HILOAD_OK;
+}
+
+HiloadResult file_watch_remove(hiFileWatcherContext *ctx, const char *path) {
+
+  size_t i = 0;
+  hiFileWatch *watch = file_watch_find_by_path(ctx, path, &i);
+  if (watch) {
+
+    // destroy parent reference. We assume it will only have one.
+    char *parent = get_parent_folder(path);
+    if (parent) {
+      hiFileWatch *pw = file_watch_find_by_path(ctx, parent, NULL);
+      if (pw) {
+        for (size_t i = 0; i < sc_array_size(&pw->files); i++) {
+          const char *fn = sc_array_at(&pw->files, i);
+          if (fn == watch->path) {
+            sc_array_del(&pw->files, i);
+            break;
+          }
+        }
+      }
+      free(parent);
+    }
+    file_watch_destroy(ctx->fd, watch);
+    sc_array_del(&ctx->watches, i);
+    return HILOAD_OK;
+  }
+  return HILOAD_FAIL;
+}

src/filewatcher/filewatch.h

@@ -0,0 +1,22 @@
+#ifndef FILEWATCH_H_
+#define FILEWATCH_H_
+
+#include "array/array.h"
+#include "filewatch_context.h"
+#include "types.h"
+
+struct hiFileWatcherContext;
+struct hiFileWatch;
+
+hiFileWatch *file_watch_find_by_wd(struct hiFileWatcherContext *ctx,
+                                         int wd, size_t *index);
+hiFileWatch *file_watch_find_by_path(struct hiFileWatcherContext *ctx,
+                                           const char *path,  size_t *index);
+
+HiloadResult file_watch_add(struct hiFileWatcherContext *ctx, u32 mask,
+                            const char *path);
+HiloadResult file_watch_remove(struct hiFileWatcherContext *ctx,
+                               const char *path);
+void file_watch_destroy_watches(struct hiFileWatcherContext *ctx);
+
+#endif // FILEWATCH_H_

src/filewatcher/filewatch_context.h

@@ -0,0 +1,35 @@
+#ifndef FILEWATCH_CONTEXT_H_
+#define FILEWATCH_CONTEXT_H_
+
+#include "array/array.h"
+#include "types.h"
+
+/**
+ * Added for each file watch call.
+ *
+ * Events and watches refer to the same string as params for efficient string
+ * comparison, but this means care has to be taken when deleting the params.
+ * Events should be cleared first.
+ */
+typedef struct {
+  const char *path; // Params own their path
+  u32 mask;
+} hiWatchParams;
+sc_array_def(hiWatchParams, fwparam);
+
+typedef struct {
+  int wd;           // Watch descriptor
+  u32 mask;         // watch mask used
+  const char *path; // inotify watch path, owning if it's a parent watcher
+  struct sc_array_str
+      files; // param paths associated with that path. Pointers to paths params.
+} hiFileWatch;
+sc_array_def(hiFileWatch, fwatch);
+
+typedef struct hiFileWatcherContext {
+  int fd;
+  struct sc_array_fwparam params;
+  struct sc_array_fwatch watches;
+} hiFileWatcherContext;
+
+#endif // FILEWATCH_CONTEXT_H_

src/filewatcher/filewatch_type.h

@@ -0,0 +1,36 @@
+#ifndef FILEWATCH_TYPE_H_
+#define FILEWATCH_TYPE_H_
+
+typedef enum {
+  HI_FILE_NONE = 0, // Used to signal invalid event
+  HI_FILE_MODIFY = 1 << 1,
+  HI_FILE_CREATE = 1 << 2,
+  HI_FILE_DELETE = 1 << 3,
+  HI_FILE_MOVE = 1 << 4,
+  HI_FILE_CHANGE =
+      (HI_FILE_MODIFY | HI_FILE_CREATE | HI_FILE_DELETE | HI_FILE_MOVE),
+  HI_FILE_ALL_EVENTS = (HI_FILE_CHANGE),
+  HI_FILE_PARENT = 1 << 31,
+} HiFileWatchType;
+
+static inline const char *hi_file_watch_type_to_str(HiFileWatchType type) {
+  switch (type) {
+  case HI_FILE_NONE:
+    return "HI_FILE_NONE";
+  case HI_FILE_MODIFY:
+    return "HI_FILE_MODIFY";
+  case HI_FILE_CREATE:
+    return "HI_FILE_CREATE";
+  case HI_FILE_DELETE:
+    return "HI_FILE_DELETE";
+  case HI_FILE_MOVE:
+    return "HI_FILE_MOVE";
+  default:
+    return "Unknown HI_FILE_TYPE";
+
+    return "Unknown HI_FILE_TYPE";
+    // clang-format on
+  }
+}
+
+#endif // FILEWATCH_TYPE_H_

src/filewatcher/filewatcher.c

@@ -2,6 +2,7 @@
 
 #include <errno.h>
 #include <stdatomic.h>
+#include <stddef.h>
 #include <string.h>
 #include <sys/inotify.h>
 #include <sys/select.h>
@@ -9,287 +10,253 @@
 #include <time.h>
 #include <unistd.h>
 
-#include "types.h"
 #include "array/array.h"
 #include "common.h"
+#include "filewatch.h"
+#include "filewatch_context.h"
+#include "filewatch_type.h"
 #include "logger/logger.h"
+#include "types.h"
 
-sc_array_def(hiFileEvent, fevent);
-
-typedef struct hiFileEvents {
-  struct sc_array_fevent events;
-} hiFileEvents;
-
-typedef struct {
-  int wd;           // Watch descriptor
-  u32 mask;         // watch mask used
-  const char *path; // Owning
-} WatchPath;
-sc_array_def(WatchPath, watch);
-
-typedef struct hiWatchPaths {
-  int fd;
-  struct sc_array_watch watches;
-} hiWatchPaths;
+sc_array_def(hiFileEvent, fwevent);
 
 typedef struct hiFileWatcher {
   thrd_t thread;
   mtx_t mutex;
   cnd_t cond;
   int running;
-  struct hiWatchPaths watchpaths;
-  struct hiFileEvents events;
+  struct hiFileWatcherContext context;
+  struct sc_array_fwevent events;
 } hiFileWatcher;
 
+/*
+ * Watch Params
+ */
+
+static inline hiWatchParams watch_params_create(const char *path, u32 mask) {
+  return (hiWatchParams){.path = strdup(path), .mask = mask};
+}
+
+static inline void watch_params_destroy(hiWatchParams *params) {
+  free((char *)params->path);
+}
+
+static hiWatchParams *watch_params_find_by_path(const char *path,
+                                                hiFileWatcherContext *ctx,
+                                                size_t *index) {
+  const struct sc_array_fwparam *params = &ctx->params;
+  for (size_t i = 0; i < sc_array_size(params); ++i) {
+    hiWatchParams *param = &sc_array_at(params, i);
+    if (strcmp(path, param->path) == 0) {
+      if (index)
+        *index = i;
+      return param;
+    }
+  }
+  return NULL;
+}
+
 /*
  * File Events
  */
 
-static hiFileEvent create_file_event(const struct inotify_event *event) {
-  hiFileEvent hievent = {0};
+#define NULL_EVENT (hiFileEvent){0};
 
-  if (!event) {
-    return hievent;
+static hiFileEvent file_event_create(const struct inotify_event *inevent,
+                                     hiFileWatcherContext *ctx) {
+  hiFileEvent event = {0};
+
+  if (!inevent) {
+    return event;
   }
 
-  if (event->len)
-    hievent.file = strdup(event->name);
+  const hiFileWatch *fw = file_watch_find_by_wd(ctx, inevent->wd, NULL);
 
-  if (has_mask(event->mask, IN_ACCESS)) {
-    hievent.type = HI_FILE_ACCESS;
-  } else if (has_mask(event->mask, IN_MODIFY)) {
-    hievent.type = HI_FILE_MODIFY;
-  } else if (has_mask(event->mask, IN_CREATE)) {
-    hievent.type = HI_FILE_CREATE;
-  } else if (has_mask(event->mask, IN_DELETE)) {
-    hievent.type = HI_FILE_DELETE;
+  if (has_mask(inevent->mask, IN_IGNORED)) {
+    sc_log_debug("IN_IGNORED received on %s\n", fw->path);
+    return NULL_EVENT;
   }
-  return hievent;
-}
 
-void hi_file_event_free(hiFileEvent *event) {
-  if (event) {
-    free((void *)event->file);
-  }
-}
+  if (inevent->len) {
+    // find if file is associated with any path
+    for (size_t i = 0; i < sc_array_size(&fw->files); ++i) {
+      const char *watched_file = sc_array_at(&fw->files, i);
+      if (strcmp(watched_file, inevent->name)) {
 
-void hi_file_event_destroy(hiFileEvent *event) {
-  if (event) {
-    free((void *)event->file);
-    memset(event, 0, sizeof(*event));
+        // check if event mask matches the watcher mask
+        hiWatchParams *params =
+            watch_params_find_by_path(watched_file, ctx, NULL);
+        if (!params) {
+          return NULL_EVENT;
+        }
+
+        if (has_mask(inevent->mask, IN_MODIFY)) {
+          event.type = HI_FILE_MODIFY;
+        } else if (has_mask(inevent->mask, IN_CREATE)) {
+          event.type = HI_FILE_CREATE;
+        } else if (has_mask(inevent->mask, IN_DELETE)) {
+          event.type = HI_FILE_DELETE;
+        } else if (has_mask(inevent->mask, IN_DELETE_SELF)) {
+          event.type = HI_FILE_DELETE;
+        } else if (has_mask(inevent->mask, IN_MOVE)) {
+          event.type = HI_FILE_MOVE;
+        }
+
+        // We aren't watching for this event on the file, discard
+        if (!has_mask(params->mask, event.type)) {
+          return NULL_EVENT;
+        }
+
+        event.pathname = watched_file;
+
+        // Event matched and we're watching for it
+        return event;
+      }
+    }
+    // Something happened with a file we're not watching
+    return NULL_EVENT;
   }
+  // Event on the folder itself
+
+  return NULL_EVENT;
 }
 
 hiFileEvent hi_file_event_pop(hiFileWatcher *ctx) {
   mtx_lock(&ctx->mutex);
-  hiFileEvent *last = &sc_array_last(&ctx->events.events);
+  hiFileEvent *last = &sc_array_last(&ctx->events);
   hiFileEvent e = *last;
 
-  // prevent destroy from freeing the file string
-  last->file = 0;
-  hi_file_event_destroy(last);
-  sc_array_del_last(&ctx->events.events);
+  sc_array_del_last(&ctx->events);
 
   mtx_unlock(&ctx->mutex);
   return e;
 }
 
-static HiloadResult file_events_init(hiFileEvents *events) {
-  sc_array_init(&events->events);
-  return HILOAD_OK;
-}
-
-static void file_events_destroy(hiFileEvents *events) {
-  if (events) {
-    for (size_t i = 0; i < sc_array_size(&events->events); ++i) {
-      hi_file_event_free(&sc_array_at(&events->events, i));
-    }
-    sc_array_term(&events->events);
-  }
-}
-
-/*
- * Watch paths
- */
-
-static inline u32 create_watch_mask(u32 flags) {
-  u32 inmask = 0;
-  if (has_mask(flags, HI_FILE_ACCESS)) {
-    inmask |= IN_ACCESS;
-  }
-  if (has_mask(flags, HI_FILE_MODIFY)) {
-    inmask |= IN_MODIFY;
-  }
-  if (has_mask(flags, HI_FILE_CREATE)) {
-    inmask |= IN_CREATE;
-  }
-  if (has_mask(flags, HI_FILE_DELETE)) {
-    inmask |= IN_DELETE;
-  }
-  return inmask;
-}
-
-static HiloadResult watch_path_add(hiWatchPaths *paths, u32 mask,
-                                   const char *path) {
-
-  if (!paths || paths->fd == -1) {
-    sc_log_error("Invalid inotify context\n");
-    return HILOAD_FAIL;
-  }
-
-  int wd = inotify_add_watch(paths->fd, path, create_watch_mask(mask));
-  if (wd == -1) {
-    sc_log_error("Couldn't watch: %s: %s\n", path, strerror(errno));
-    return HILOAD_FAIL;
-  }
-
-  {
-    WatchPath wp = {.wd = wd, .mask = mask, .path = strdup(path)};
-    sc_array_add(&paths->watches, wp);
-  }
-
-  return HILOAD_OK;
-}
-
-static void watch_path_destroy(int fd, WatchPath *wf) {
-  inotify_rm_watch(fd, wf->wd);
-  free((void *)wf->path);
-
-  wf->wd = -1;
-  wf->path = NULL;
-}
-
-static HiloadResult watch_path_remove(hiWatchPaths *paths, const char *path) {
-
-  bool found = false;
-  {
-    for (size_t i = 0; i < sc_array_size(&paths->watches); ++i) {
-      WatchPath *wp = &sc_array_at(&paths->watches, i);
-      if (strcmp(wp->path, path) == 0) {
-        watch_path_destroy(paths->fd, wp);
-        sc_array_del(&paths->watches, i);
-        found = true;
-        break;
-      }
-    }
-  }
-  return found ? HILOAD_OK : HILOAD_FAIL;
-}
-
-static HiloadResult watch_paths_init(hiWatchPaths *paths) {
-
-  paths->fd = inotify_init1(IN_CLOEXEC | IN_NONBLOCK);
-  if (paths->fd == -1) {
-    return HILOAD_FAIL;
-  }
-
-  sc_array_init(&paths->watches);
-  return HILOAD_OK;
-}
-
-static void watch_paths_destroy(hiWatchPaths *paths) {
-  if (paths) {
-    for (size_t i = 0; i < sc_array_size(&paths->watches); i++) {
-      WatchPath *wp = &sc_array_at(&paths->watches, i);
-      watch_path_destroy(paths->fd, wp);
-    }
-    sc_array_term(&paths->watches);
-  }
-}
-
 /*
  * File Watcher
  */
 
+static HiloadResult file_watcher_ctx_init(hiFileWatcherContext *ctx) {
+
+  ctx->fd = inotify_init1(IN_CLOEXEC | IN_NONBLOCK);
+  if (ctx->fd == -1) {
+    return HILOAD_FAIL;
+  }
+
+  sc_array_init(&ctx->watches);
+  sc_array_init(&ctx->params);
+  return HILOAD_OK;
+}
+
+static void file_watcher_ctx_destroy(hiFileWatcherContext *ctx) {
+  if (ctx) {
+    file_watch_destroy_watches(ctx);
+  }
+}
+
 // Declare the thread func
 int file_watcher_watch(void *arg);
 
 hiFileWatcher *hi_file_watcher_create() {
 
   // Allocate context
-  hiFileWatcher *context = malloc(sizeof(hiFileWatcher));
-  memset(context, 0, sizeof(hiFileWatcher));
+  hiFileWatcher *fw = malloc(sizeof(hiFileWatcher));
+  memset(fw, 0, sizeof(hiFileWatcher));
 
-  if (context) {
-    if (!HILOADRES(watch_paths_init(&context->watchpaths))) {
+  if (fw) {
+    if (!HILOADRES(file_watcher_ctx_init(&fw->context))) {
       sc_log_error("Failed to initialize watch paths\n");
-      if (context->watchpaths.fd == -1) {
+      if (fw->context.fd == -1) {
         sc_log_error("Couldn't initialize inotify\n");
       }
-      free(context);
+      free(fw);
       return NULL;
     }
-
-    if (!HILOADRES(file_events_init(&context->events))) {
-      sc_log_error("Failed to initialize file events\n");
-      free(context);
-      return NULL;
-    }
-
-    mtx_init(&context->mutex, mtx_plain);
-    cnd_init(&context->cond);
-    context->running = true;
-    thrd_create(&context->thread, file_watcher_watch, context);
-    return context;
+    sc_array_init(&fw->events);
+    mtx_init(&fw->mutex, mtx_plain);
+    cnd_init(&fw->cond);
+    fw->running = true;
+    thrd_create(&fw->thread, file_watcher_watch, fw);
+    return fw;
   }
-  free(context);
+  free(fw);
   return NULL;
 }
 
-HiloadResult hi_file_watcher_add(struct hiFileWatcher *ctx,
-                                 const char *filename, u32 flags) {
-  if (!ctx) {
+HiloadResult hi_file_watcher_add(struct hiFileWatcher *fw, const char *filename,
+                                 u32 flags) {
+  if (!fw) {
     sc_log_error("Attempted to add file watcher for '%s' with null context\n",
                  filename);
     return HILOAD_FAIL;
   }
 
-  mtx_lock(&ctx->mutex);
-  if (!HILOADRES(watch_path_add(&ctx->watchpaths, flags, filename))) {
-    mtx_unlock(&ctx->mutex);
+  mtx_lock(&fw->mutex);
+
+  if (!HILOADRES(file_watch_add(&fw->context, flags, filename))) {
+    mtx_unlock(&fw->mutex);
     return HILOAD_FAIL;
   }
-  mtx_unlock(&ctx->mutex);
+  {
+    // Add watch param as well
+    hiWatchParams *params =
+        watch_params_find_by_path(filename, &fw->context, NULL);
+    if (!params) {
+      hiWatchParams params = watch_params_create(filename, flags);
+      sc_array_add(&fw->context.params, params);
+    } else {
+      params->mask |= flags;
+    }
+  }
 
-  sc_log_info("Watching file: %s\n", filename);
+  mtx_unlock(&fw->mutex);
   return HILOAD_OK;
 }
 
-HiloadResult hi_file_watcher_remove(struct hiFileWatcher *ctx,
+HiloadResult hi_file_watcher_remove(struct hiFileWatcher *fw,
                                     const char *filename) {
-  if (!ctx) {
+  if (!fw) {
     return HILOAD_FAIL;
   }
 
-  mtx_lock(&ctx->mutex);
-  if (!HILOADRES(watch_path_remove(&ctx->watchpaths, filename))) {
-    mtx_unlock(&ctx->mutex);
+  mtx_lock(&fw->mutex);
+  if (!HILOADRES(file_watch_remove(&fw->context, filename))) {
+    mtx_unlock(&fw->mutex);
     return HILOAD_FAIL;
   }
 
-  mtx_unlock(&ctx->mutex);
+  {
+    // remove watchparam as well
+    size_t i = 0;
+    hiWatchParams *params =
+        watch_params_find_by_path(filename, &fw->context, &i);
+    watch_params_destroy(params);
+    sc_array_del(&fw->context.params, i);
+  }
+
+  mtx_unlock(&fw->mutex);
   sc_log_info("Removed file: '%s' from watch, filename");
   return HILOAD_OK;
 }
 
-void hi_file_watcher_notify(hiFileWatcher *ctx) {
-  if (ctx && ctx->running) {
-    cnd_signal(&ctx->cond);
+void hi_file_watcher_notify(hiFileWatcher *fw) {
+  if (fw && fw->running) {
+    cnd_signal(&fw->cond);
   }
 }
 
-void hi_file_watcher_destroy(hiFileWatcher *ctx) {
-  if (!ctx)
+void hi_file_watcher_destroy(hiFileWatcher *fw) {
+  if (!fw)
     return;
 
-  if (ctx->running) {
-    ctx->running = false;
-    hi_file_watcher_notify(ctx);
-    thrd_join(ctx->thread, NULL);
+  if (fw->running) {
+    fw->running = false;
+    hi_file_watcher_notify(fw);
+    thrd_join(fw->thread, NULL);
   }
-  file_events_destroy(&ctx->events);
-  watch_paths_destroy(&ctx->watchpaths);
-  free(ctx);
+
+  file_watcher_ctx_destroy(&fw->context);
+  free(fw);
 }
 
 int file_watcher_watch(void *arg) {
@@ -304,7 +271,7 @@ int file_watcher_watch(void *arg) {
   while (ctx->running) {
     ssize_t n;
 
-    n = read(ctx->watchpaths.fd, buf, sizeof(buf));
+    n = read(ctx->context.fd, buf, sizeof(buf));
     if (n == -1 && errno != EAGAIN) {
       sc_log_error("Failed to read inotify: %s. Exiting thread.\n",
                    strerror(errno));
@@ -316,8 +283,13 @@ int file_watcher_watch(void *arg) {
            ptr += sizeof(struct inotify_event) + event->len) {
 
         event = (const struct inotify_event *)ptr;
-        hiFileEvent e = create_file_event(event);
-        sc_array_add(&ctx->events.events, e);
+        hiFileEvent e = file_event_create(event, &ctx->context);
+        sc_array_add(&ctx->events, e);
+
+        if (event->len) {
+          sc_log_debug("Event created: queue-size: %u, %s: %s\n", sc_array_size(&ctx->events),
+                       e.pathname, hi_file_watch_type_to_str(e.type));
+        }
       }
       continue; // read again without waiting
     }

src/filewatcher/filewatcher.h

@@ -1,27 +1,25 @@
 #ifndef HI_FILEWATCHER_H_
 #define HI_FILEWATCHER_H_
 
+#include "filewatch_type.h"
 #include "types.h"
 
 /**
- * File event watching related functionality and types
+ * File event watcher using inotify.
  */
 
-typedef enum {
-  HI_FILE_NONE = 0,
-  HI_FILE_ACCESS = 1 << 0,
-  HI_FILE_MODIFY = 1 << 1,
-  HI_FILE_CREATE = 1 << 2,
-  HI_FILE_DELETE = 1 << 3,
-  HI_FILE_ALL =
-      (HI_FILE_ACCESS | HI_FILE_MODIFY | HI_FILE_CREATE | HI_FILE_DELETE)
-} HiFileEventType;
 
+/**
+ * File Event produced by FileWatcher.
+ *
+ * As long as the event queue is cleared before making modifications to the File
+ * Watcher, pointers are safe to use and don't need freeing, as they refer to
+ * memory inside the file watcher struct.
+ */
 typedef struct {
-  const char *watcher; // Path given to the corresponding wd. Not owning.
-  const char *file; // Owning, should be freed by the event handler by calling
-                    // `hi_file_event_destroy`)
-  HiFileEventType type;
+  const char *pathname; // Pathname given with the `hi_file_watcher_add` call.
+                        // Do not free.
+  HiFileWatchType type;
 } hiFileEvent;
 
 struct hiFileWatcher;
@@ -60,18 +58,10 @@ HiloadResult hi_file_watcher_add(struct hiFileWatcher *context,
  */
 void hi_file_watcher_notify(struct hiFileWatcher *context);
 
-/**
- * Frees held memory but doesn't zero fields
- */
-void hi_file_event_free(hiFileEvent *event);
 /**
  * Pop an event from event stack. Call `hi_file_event_destroy` when done with
  * it.
  */
 hiFileEvent hi_file_event_pop(struct hiFileWatcher *ctx);
-/**
- * Free and zero held memory. Call after pop.
- */
-void hi_file_event_destroy(hiFileEvent *event);
 
 #endif // HI_FILEWATCHER_H_

src/hiload.c

@@ -2,11 +2,12 @@
 
 #include "array/sc_array.h"
 #include "filewatcher/filewatcher.h"
+#include "logger/logger.h"
+#include "logger/sc_log.h"
 #include "memory.h"
 #include "string/string.h"
 #include "symbols.h"
 #include "types.h"
-#include "logger/logger.h"
 
 #include <assert.h>
 #include <dlfcn.h>
@@ -31,56 +32,62 @@ typedef struct {
   struct sc_array_memreg memory_regions;
   struct sc_array_str enabled_modules;
   struct hiFileWatcher *filewatcher;
+  ModuleInfos *loaded_modules;
 } HiloadContext;
 
 static HiloadContext context = {0};
-static ModuleInfos *module_infos = 0;
 
 // Callback function for dl_iterate_phdr
 static int gather_module_infos_callback(struct dl_phdr_info *info, size_t size,
                                         void *data) {
 
-  ModuleInfos *infos = (ModuleInfos *)data;
+  ModuleInfos *mod_infos = (ModuleInfos *)data;
 
   // Store the module name
   const char *modname = info->dlpi_name;
-  sc_array_add(&infos->names, strdup(modname));
-  for (size_t i = 0; i < sc_array_size(&context.enabled_modules); i++) {
-
-    if (hi_path_has_filename(modname,
-                             sc_array_at(&context.enabled_modules, i))) {
-      if (!HILOADRES(
-              hi_file_watcher_add(context.filewatcher, modname, HI_FILE_ALL))) {
-        sc_log_error("Failed to set filewatcher for: '%s'\n", modname);
-      }
-    }
-  }
+  sc_array_add(&mod_infos->names, strdup(modname));
 
   sc_log_info("Processing: '%s'\n", info->dlpi_name);
 
   // Try to get the handle
   void *handle = dlopen(info->dlpi_name, RTLD_LAZY | RTLD_NOLOAD);
   assert(handle);
-  infos->count++;
+  mod_infos->count++;
 
-  sc_array_add(&infos->handles, handle);
-  sc_array_add(&infos->addresses, info->dlpi_addr);
+  sc_array_add(&mod_infos->handles, handle);
+  sc_array_add(&mod_infos->addresses, info->dlpi_addr);
   sc_log_debug("  size: %u\n", size);
-  sc_log_debug("  handle: %p\n", sc_array_last(&infos->handles));
+  sc_log_debug("  handle: %p\n", sc_array_last(&mod_infos->handles));
   sc_log_debug("  dlpi_addr: %p\n", info->dlpi_addr);
   sc_log_debug("  dlpi_tls_modid: %zu\n", info->dlpi_tls_modid);
   sc_log_debug("  dlpi_tls_data: %p\n", info->dlpi_tls_data);
 
   Dl_info dl_info = {0};
-  if (!dladdr((void *)sc_array_last(&infos->addresses), &dl_info)) {
-    sc_log_error("Couldn't load dlinfo for %s: %s\n",
-                 (sc_array_last(&infos->names)), dlerror());
-  }
-  sc_log_debug("    dli_fname: %s\n", dl_info.dli_fname);
-  sc_log_debug("    dli_fbase: %p\n", dl_info.dli_fbase);
+  if (dladdr((void *)sc_array_last(&mod_infos->addresses), &dl_info)) {
 
-  SymbolInfos symbol_info = {0};
-  sc_array_add(&infos->symbols, symbol_info);
+    // Check if it's in the provided watchlist and add a watcher
+    for (size_t i = 0; i < sc_array_size(&context.enabled_modules); i++) {
+
+      if (hi_path_has_filename(modname,
+                               sc_array_at(&context.enabled_modules, i))) {
+
+        const char *filename = modname;
+        if (strcmp(modname, "") == 0) {
+          // The executable itself. Name needs to be resolved for filewatcher
+          filename = dl_info.dli_fname;
+        }
+        if (!HILOADRES(hi_file_watcher_add(context.filewatcher, filename,
+                                           HI_FILE_ALL_EVENTS))) {
+          sc_log_error("Failed to set filewatcher for: '%s'\n", filename);
+        } else {
+          sc_log_info("Watching file: %s\n", filename);
+        }
+      }
+    }
+  } else {
+    sc_log_error("Couldn't load dlinfo for %s: %s\n",
+                 (sc_array_last(&mod_infos->names)), dlerror());
+  }
 
   return 0; // Continue iteration
 }
@@ -186,44 +193,50 @@ static ReloadResult reload_solib(ModuleInfos *modules, const char *filename,
 }
 
 ReloadResult hi_reload_solib(const char *module_name) {
-  assert(module_infos);
 
   void *new_handle = NULL;
-  ReloadResult result = reload_solib(module_infos, module_name, &new_handle);
+  ReloadResult result =
+      reload_solib(context.loaded_modules, module_name, &new_handle);
 
   return result;
 }
 
-void hi_print_module_infos() {
-  assert(module_infos);
+void hi_print_loaded_modules(void) {
 
-  const ModuleInfos *modules = module_infos;
-  if (!modules) {
+  sc_log_info("Loaded module info:\n");
+  sc_log_info("-------------------\n");
+
+  const ModuleInfos *mod_infos = context.loaded_modules;
+  if (!mod_infos) {
     sc_log_error("No module information available.\n");
     return;
   }
 
-  sc_log_info("Found %zu loaded modules:\n", modules->count);
+  sc_log_info("Found %zu loaded modules:\n", mod_infos->count);
 
-  for (size_t i = 0; i < modules->count; i++) {
+  for (size_t i = 0; i < mod_infos->count; i++) {
 
-    sc_log_debug("'%s'\n", sc_array_at(&modules->names, i));
-    sc_log_debug("  handle: %p\n", sc_array_at(&modules->handles, i));
-    sc_log_debug("  address: %p\n", sc_array_at(&modules->addresses, i));
+    sc_log_info("'%s'\n", sc_array_at(&mod_infos->names, i));
+    sc_log_info("  handle: %p\n", sc_array_at(&mod_infos->handles, i));
+    sc_log_info("  address: %p\n", sc_array_at(&mod_infos->addresses, i));
 
-    const SymbolInfos *symbols = &sc_array_at(&modules->symbols, i);
-    for (size_t j = 0; j < sc_array_size(&symbols->names); j++) {
-      const void *addr = sc_array_at(&symbols->addresses, j);
-      const char *name = sc_array_at(&symbols->names, j);
-      sc_log_debug("  %p: %s\n", addr, name);
+    // If we have loaded symbols, print those
+    if (sc_array_size(&mod_infos->symbols) > 0) {
+      const SymbolInfos *symbols = &sc_array_at(&mod_infos->symbols, i);
+      if (symbols) {
+        for (size_t j = 0; j < sc_array_size(&symbols->names); j++) {
+          const void *addr = sc_array_at(&symbols->addresses, j);
+          const char *name = sc_array_at(&symbols->names, j);
+          sc_log_info("  %p: %s\n", addr, name);
+        }
+      }
     }
 
-    sc_log_debug("\n");
+    sc_log_info("\n");
   }
 }
 
 int hi_init(unsigned n, const char **enabled_modules) {
-  assert(!module_infos);
 
   if (sc_log_init() != 0) {
     fprintf(stderr, "Failed to init logger.\n");
@@ -253,17 +266,19 @@ int hi_init(unsigned n, const char **enabled_modules) {
   }
 
   // Override existing
-  if (module_infos) {
-    module_infos_free(module_infos);
+  if (context.loaded_modules) {
+    module_infos_free(context.loaded_modules);
   }
 
-  module_infos = infos;
-  hi_print_module_infos();
+  context.loaded_modules = infos;
+  hi_print_loaded_modules();
 
   return 0;
 }
 
 void hi_deinit() {
-  module_infos_free(module_infos);
+  module_infos_free(context.loaded_modules);
+  hi_file_watcher_destroy(context.filewatcher);
   sc_log_term();
+  memset(&context, 0, sizeof(context));
 }

src/memory.c

@@ -53,7 +53,7 @@ HiloadResult read_memory_maps_self(struct sc_array_memreg *regions) {
     char pathname[256];
 
     // clang-format off
-    // Example from `cat /proc/self/maps`
+    // Format example from the file:
     // 7fa0b66ca000-7fa0b66cc000 rw-p 00033000 fe:02 28063911 /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2
     int result = sscanf(line, "%lx-%lx %4s %lx %x:%x %lu %255s",
                         &reg.region_start,

test/manual/minimal.cpp

@@ -19,7 +19,7 @@ int main(int argc, char *argv[]) {
     printf("minimal_lib::getNewValue address: %p\n", minimal_lib::getNewValue);
     printf("minimal_lib::otherValue address: %p\n", &minimal_lib::otherValue);
     printf("==========================\n");
-    printf("\n");
+    printf("");
 
     modified = minimal_lib::getNewValue(5);
     printf("getModified(5): %d\n", modified);

test/manual/minimal_lib.cpp

@@ -3,7 +3,7 @@
 namespace minimal_lib {
 
 int getNewValue(int x) {
-  static int value = 0;
+  static int value = 1;
   value = value + x;
   return value;
 }