Snapshot of commit d5ec1d5018ed24f1b4f32b1d09df6dbd7e2fc425

from branch master of git://git.jetbrains.org/idea/community.git
diff --git a/native/fsNotifier/linux/main.c b/native/fsNotifier/linux/main.c
new file mode 100644
index 0000000..606e914
--- /dev/null
+++ b/native/fsNotifier/linux/main.c
@@ -0,0 +1,441 @@
+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "fsnotifier.h"
+
+#include <errno.h>
+#include <limits.h>
+#include <mntent.h>
+#include <paths.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/inotify.h>
+#include <sys/select.h>
+#include <syslog.h>
+#include <unistd.h>
+
+#define LOG_ENV "FSNOTIFIER_LOG_LEVEL"
+#define LOG_ENV_DEBUG "debug"
+#define LOG_ENV_INFO "info"
+#define LOG_ENV_WARNING "warning"
+#define LOG_ENV_ERROR "error"
+#define LOG_ENV_OFF "off"
+
+#define VERSION "1.2"
+#define VERSION_MSG "fsnotifier " VERSION "\n"
+
+#define USAGE_MSG \
+    "fsnotifier - IntelliJ IDEA companion program for watching and reporting file and directory structure modifications.\n\n" \
+    "fsnotifier utilizes \"user\" facility of syslog(3) - messages usually can be found in /var/log/user.log.\n" \
+    "Verbosity is regulated via " LOG_ENV " environment variable, possible values are: " \
+    LOG_ENV_DEBUG ", " LOG_ENV_INFO ", " LOG_ENV_WARNING ", " LOG_ENV_ERROR ", " LOG_ENV_OFF "; latter is the default.\n\n" \
+    "Use 'fsnotifier --selftest' to perform some self-diagnostics (output will be logged and printed to console).\n"
+
+#define HELP_MSG \
+    "Try 'fsnotifier --help' for more information.\n"
+
+#define INOTIFY_LIMIT_MSG \
+    "The current <b>inotify</b>(7) watch limit of %d is too low. " \
+    "<a href=\"http://confluence.jetbrains.net/display/IDEADEV/Inotify+Watches+Limit\">More details.</a>\n"
+
+typedef struct {
+  char* name;
+  int id;
+} watch_root;
+
+static array* roots = NULL;
+
+static bool show_warning = true;
+static bool self_test = false;
+
+static void init_log();
+static void run_self_test();
+static void main_loop();
+static bool read_input();
+static bool update_roots(array* new_roots);
+static void unregister_roots();
+static bool register_roots(array* new_roots, array* unwatchable, array* mounts);
+static array* unwatchable_mounts();
+static void inotify_callback(char* path, int event);
+static void output(const char* format, ...);
+
+
+int main(int argc, char** argv) {
+  if (argc > 1) {
+    if (strcmp(argv[1], "--help") == 0) {
+      printf(USAGE_MSG);
+      return 0;
+    }
+    else if (strcmp(argv[1], "--version") == 0) {
+      printf(VERSION_MSG);
+      return 0;
+    }
+    else if (strcmp(argv[1], "--selftest") == 0) {
+      self_test = true;
+    }
+    else {
+      printf("unrecognized option: %s\n", argv[1]);
+      printf(HELP_MSG);
+      return 1;
+    }
+  }
+
+  init_log();
+  if (!self_test) {
+    userlog(LOG_INFO, "started (v." VERSION ")");
+  }
+  else {
+    userlog(LOG_INFO, "started (self-test mode) (v." VERSION ")");
+  }
+
+  setvbuf(stdin, NULL, _IONBF, 0);
+  setvbuf(stdout, NULL, _IONBF, 0);
+
+  roots = array_create(20);
+  if (init_inotify() && roots != NULL) {
+    set_inotify_callback(&inotify_callback);
+
+    if (!self_test) {
+      main_loop();
+    }
+    else {
+      run_self_test();
+    }
+
+    unregister_roots();
+  }
+  else {
+    printf("GIVEUP\n");
+  }
+  close_inotify();
+  array_delete(roots);
+
+  userlog(LOG_INFO, "finished");
+  closelog();
+
+  return 0;
+}
+
+
+static void init_log() {
+  char* env_level = getenv(LOG_ENV);
+  int level = LOG_EMERG;
+  if (env_level != NULL) {
+    if (strcmp(env_level, LOG_ENV_DEBUG) == 0)  level = LOG_DEBUG;
+    else if (strcmp(env_level, LOG_ENV_INFO) == 0)  level = LOG_INFO;
+    else if (strcmp(env_level, LOG_ENV_WARNING) == 0)  level = LOG_WARNING;
+    else if (strcmp(env_level, LOG_ENV_ERROR) == 0)  level = LOG_ERR;
+  }
+
+  if (self_test) {
+    level = LOG_DEBUG;
+  }
+
+  char ident[32];
+  snprintf(ident, sizeof(ident), "fsnotifier[%d]", getpid());
+  openlog(ident, 0, LOG_USER);
+  setlogmask(LOG_UPTO(level));
+}
+
+
+void userlog(int priority, const char* format, ...) {
+  va_list ap;
+
+  va_start(ap, format);
+  vsyslog(priority, format, ap);
+  va_end(ap);
+
+  if (self_test) {
+    const char* level = "debug";
+    switch (priority) {
+      case LOG_ERR:  level = "error"; break;
+      case LOG_WARNING:  level = " warn"; break;
+      case LOG_INFO:  level = " info"; break;
+    }
+    printf("fsnotifier[%d] %s: ", getpid(), level);
+
+    va_start(ap, format);
+    vprintf(format, ap);
+    va_end(ap);
+
+    printf("\n");
+  }
+}
+
+
+static void run_self_test() {
+  array* test_roots = array_create(1);
+  char* cwd = malloc(PATH_MAX);
+  if (getcwd(cwd, PATH_MAX) == NULL) {
+    strncpy(cwd, ".", PATH_MAX);
+  }
+  array_push(test_roots, cwd);
+  update_roots(test_roots);
+}
+
+
+static void main_loop() {
+  int input_fd = fileno(stdin), inotify_fd = get_inotify_fd();
+  int nfds = (inotify_fd > input_fd ? inotify_fd : input_fd) + 1;
+  fd_set rfds;
+  bool go_on = true;
+
+  while (go_on) {
+    FD_ZERO(&rfds);
+    FD_SET(input_fd, &rfds);
+    FD_SET(inotify_fd, &rfds);
+    if (select(nfds, &rfds, NULL, NULL, NULL) < 0) {
+      userlog(LOG_ERR, "select: %s", strerror(errno));
+      go_on = false;
+    }
+    else if (FD_ISSET(input_fd, &rfds)) {
+      go_on = read_input();
+    }
+    else if (FD_ISSET(inotify_fd, &rfds)) {
+      go_on = process_inotify_input();
+    }
+  }
+}
+
+
+static bool read_input() {
+  char* line = read_line(stdin);
+  userlog(LOG_DEBUG, "input: %s", (line ? line : "<null>"));
+
+  if (line == NULL || strcmp(line, "EXIT") == 0) {
+    userlog(LOG_INFO, "exiting: %s", line);
+    return false;
+  }
+
+  if (strcmp(line, "ROOTS") == 0) {
+    array* new_roots = array_create(20);
+    CHECK_NULL(new_roots, false);
+
+    while (1) {
+      line = read_line(stdin);
+      userlog(LOG_DEBUG, "input: %s", (line ? line : "<null>"));
+      if (line == NULL || strlen(line) == 0) {
+        return false;
+      }
+      else if (strcmp(line, "#") == 0) {
+        break;
+      }
+      else {
+        int l = strlen(line);
+        if (l > 1 && line[l-1] == '/')  line[l-1] = '\0';
+        CHECK_NULL(array_push(new_roots, strdup(line)), false);
+      }
+    }
+
+    return update_roots(new_roots);
+  }
+
+  userlog(LOG_INFO, "unrecognised command: %s", line);
+  return true;
+}
+
+
+static bool update_roots(array* new_roots) {
+  userlog(LOG_INFO, "updating roots (curr:%d, new:%d)", array_size(roots), array_size(new_roots));
+
+  unregister_roots();
+
+  if (array_size(new_roots) == 0) {
+    output("UNWATCHEABLE\n#\n");
+    array_delete(new_roots);
+    return true;
+  }
+  else if (array_size(new_roots) == 1 && strcmp(array_get(new_roots, 0), "/") == 0) {  // refuse to watch entire tree
+    output("UNWATCHEABLE\n/\n#\n");
+    userlog(LOG_INFO, "unwatchable: /");
+    array_delete_vs_data(new_roots);
+    return true;
+  }
+
+  array* mounts = unwatchable_mounts();
+  if (mounts == NULL) {
+    return false;
+  }
+
+  array* unwatchable = array_create(20);
+  if (!register_roots(new_roots, unwatchable, mounts)) {
+    return false;
+  }
+
+  output("UNWATCHEABLE\n");
+  for (int i=0; i<array_size(unwatchable); i++) {
+    char* s = array_get(unwatchable, i);
+    output("%s\n", s);
+    userlog(LOG_INFO, "unwatchable: %s", s);
+  }
+  output("#\n");
+
+  array_delete_vs_data(unwatchable);
+  array_delete_vs_data(mounts);
+  array_delete_vs_data(new_roots);
+
+  return true;
+}
+
+
+static void unregister_roots() {
+  watch_root* root;
+  while ((root = array_pop(roots)) != NULL) {
+    userlog(LOG_INFO, "unregistering root: %s", root->name);
+    unwatch(root->id);
+    free(root->name);
+    free(root);
+  };
+}
+
+
+static bool register_roots(array* new_roots, array* unwatchable, array* mounts) {
+  for (int i=0; i<array_size(new_roots); i++) {
+    char* new_root = array_get(new_roots, i);
+    char* unflattened = new_root;
+    if (unflattened[0] == '|') ++unflattened;
+    userlog(LOG_INFO, "registering root: %s", new_root);
+
+    if (unflattened[0] != '/') {
+      userlog(LOG_WARNING, "  ... not valid, skipped");
+      continue;
+    }
+
+    array* inner_mounts = array_create(5);
+    CHECK_NULL(inner_mounts, false);
+
+    bool skip = false;
+    for (int j=0; j<array_size(mounts); j++) {
+      char* mount = array_get(mounts, j);
+      if (is_parent_path(mount, unflattened)) {
+        userlog(LOG_DEBUG, "watch root '%s' is under mount point '%s' - skipping", unflattened, mount);
+        CHECK_NULL(array_push(unwatchable, strdup(unflattened)), false);
+        skip = true;
+        break;
+      }
+      else if (is_parent_path(unflattened, mount)) {
+        userlog(LOG_DEBUG, "watch root '%s' contains mount point '%s' - partial watch", unflattened, mount);
+        char* copy = strdup(mount);
+        CHECK_NULL(array_push(unwatchable, copy), false);
+        CHECK_NULL(array_push(inner_mounts, copy), false);
+      }
+    }
+    if (skip) {
+      continue;
+    }
+
+    int id = watch(new_root, inner_mounts);
+    array_delete(inner_mounts);
+
+    if (id >= 0) {
+      watch_root* root = malloc(sizeof(watch_root));
+      CHECK_NULL(root, false);
+      root->id = id;
+      root->name = strdup(new_root);
+      CHECK_NULL(root->name, false);
+      CHECK_NULL(array_push(roots, root), false);
+    }
+    else if (id == ERR_ABORT) {
+      return false;
+    }
+    else if (id != ERR_IGNORE) {
+      if (show_warning && watch_limit_reached()) {
+        int limit = get_watch_count();
+        userlog(LOG_WARNING, "watch limit (%d) reached", limit);
+        output("MESSAGE\n" INOTIFY_LIMIT_MSG, limit);
+        show_warning = false;  // warn only once
+      }
+      CHECK_NULL(array_push(unwatchable, strdup(unflattened)), false);
+    }
+  }
+
+  return true;
+}
+
+
+static bool is_watchable(const char* fs) {
+  // don't watch special and network filesystems
+  return !(strncmp(fs, "dev", 3) == 0 || strcmp(fs, "proc") == 0 || strcmp(fs, "sysfs") == 0 || strcmp(fs, MNTTYPE_SWAP) == 0 ||
+           strncmp(fs, "fuse", 4) == 0 || strcmp(fs, "cifs") == 0 || strcmp(fs, MNTTYPE_NFS) == 0);
+}
+
+static array* unwatchable_mounts() {
+  FILE* mtab = setmntent(_PATH_MOUNTED, "r");
+  if (mtab == NULL) {
+    userlog(LOG_ERR, "cannot open " _PATH_MOUNTED);
+    return NULL;
+  }
+
+  array* mounts = array_create(20);
+  CHECK_NULL(mounts, NULL);
+
+  struct mntent* ent;
+  while ((ent = getmntent(mtab)) != NULL) {
+    userlog(LOG_DEBUG, "mtab: %s : %s", ent->mnt_dir, ent->mnt_type);
+    if (strcmp(ent->mnt_type, MNTTYPE_IGNORE) != 0 && !is_watchable(ent->mnt_type)) {
+      CHECK_NULL(array_push(mounts, strdup(ent->mnt_dir)), NULL);
+    }
+  }
+
+  endmntent(mtab);
+  return mounts;
+}
+
+
+static void inotify_callback(char* path, int event) {
+  if (event & IN_CREATE || event & IN_MOVED_TO) {
+    output("CREATE\n%s\nCHANGE\n%s\n", path, path);
+    userlog(LOG_DEBUG, "CREATE: %s", path);
+    return;
+  }
+
+  if (event & IN_MODIFY) {
+    output("CHANGE\n%s\n", path);
+    userlog(LOG_DEBUG, "CHANGE: %s", path);
+    return;
+  }
+
+  if (event & IN_ATTRIB) {
+    output("STATS\n%s\n", path);
+    userlog(LOG_DEBUG, "STATS: %s", path);
+    return;
+  }
+
+  if (event & IN_DELETE || event & IN_MOVED_FROM) {
+    output("DELETE\n%s\n", path);
+    userlog(LOG_DEBUG, "DELETE: %s", path);
+    return;
+  }
+
+  if (event & IN_UNMOUNT) {
+    output("RESET\n");
+    userlog(LOG_DEBUG, "RESET");
+    return;
+  }
+}
+
+
+static void output(const char* format, ...) {
+  if (self_test) {
+    return;
+  }
+
+  va_list ap;
+  va_start(ap, format);
+  vprintf(format, ap);
+  va_end(ap);
+}