1 files changed, 169 insertions, 0 deletions
diff --git a/src/log.c b/src/log.c
new file mode 100644
index 0000000..eb5d188
--- /dev/null
+++ b/src/log.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright (c) 2020 rxi
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "log.h"
+
+#define MAX_CALLBACKS 32
+
+typedef struct {
+  log_LogFn fn;
+  void *udata;
+  int level;
+} Callback;
+
+static struct {
+  void *udata;
+  log_LockFn lock;
+  int level;
+  bool quiet;
+  Callback callbacks[MAX_CALLBACKS];
+} L;
+
+
+static const char *level_strings[] = {
+  "TRACE", "DEBUG", "INFO", "WARN", "ERROR", "FATAL"
+};
+
+#ifdef LOG_USE_COLOR
+static const char *level_colors[] = {
+  "\x1b[94m", "\x1b[36m", "\x1b[32m", "\x1b[33m", "\x1b[31m", "\x1b[35m"
+};
+#endif
+
+
+static void stdout_callback(log_Event *ev) {
+  char buf[16];
+  buf[strftime(buf, sizeof(buf), "%H:%M:%S", ev->time)] = '\0';
+#ifdef LOG_USE_COLOR
+  fprintf(
+    ev->udata, "%s %s%-5s\x1b[0m \x1b[90m%s:%s:%d:\x1b[0m ",
+    buf, level_colors[ev->level], level_strings[ev->level],
+    ev->file, ev->func, ev->line);
+#else
+  fprintf(
+    ev->udata, "%s %-5s %s:%s:%d: ",
+    buf, level_strings[ev->level], ev->file, ev->func, ev->line);
+#endif
+  vfprintf(ev->udata, ev->fmt, ev->ap);
+  fprintf(ev->udata, "\n");
+  fflush(ev->udata);
+}
+
+
+static void file_callback(log_Event *ev) {
+  char buf[64];
+  buf[strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", ev->time)] = '\0';
+  fprintf(
+    ev->udata, "%s %-5s %s:%d: ",
+    buf, level_strings[ev->level], ev->file, ev->line);
+  vfprintf(ev->udata, ev->fmt, ev->ap);
+  fprintf(ev->udata, "\n");
+  fflush(ev->udata);
+}
+
+
+static void lock(void)   {
+  if (L.lock) { L.lock(true, L.udata); }
+}
+
+
+static void unlock(void) {
+  if (L.lock) { L.lock(false, L.udata); }
+}
+
+
+const char* log_level_string(int level) {
+  return level_strings[level];
+}
+
+
+void log_set_lock(log_LockFn fn, void *udata) {
+  L.lock = fn;
+  L.udata = udata;
+}
+
+
+void log_set_level(int level) {
+  L.level = level;
+}
+
+
+void log_set_quiet(bool enable) {
+  L.quiet = enable;
+}
+
+
+int log_add_callback(log_LogFn fn, void *udata, int level) {
+  for (int i = 0; i < MAX_CALLBACKS; i++) {
+    if (!L.callbacks[i].fn) {
+      L.callbacks[i] = (Callback) { fn, udata, level };
+      return 0;
+    }
+  }
+  return -1;
+}
+
+
+int log_add_fp(FILE *fp, int level) {
+  return log_add_callback(file_callback, fp, level);
+}
+
+
+static void init_event(log_Event *ev, void *udata) {
+  if (!ev->time) {
+    time_t t = time(NULL);
+    ev->time = localtime(&t);
+  }
+  ev->udata = udata;
+}
+
+
+void log_log(int level, const char *file, const char *func, int line, const char *fmt, ...) {
+  log_Event ev = {
+    .fmt   = fmt,
+    .file  = file,
+    .func  = func,
+    .line  = line,
+    .level = level,
+  };
+
+  lock();
+
+  if (!L.quiet && level >= L.level) {
+    init_event(&ev, stderr);
+    va_start(ev.ap, fmt);
+    stdout_callback(&ev);
+    va_end(ev.ap);
+  }
+
+  for (int i = 0; i < MAX_CALLBACKS && L.callbacks[i].fn; i++) {
+    Callback *cb = &L.callbacks[i];
+    if (level >= cb->level) {
+      init_event(&ev, cb->udata);
+      va_start(ev.ap, fmt);
+      cb->fn(&ev);
+      va_end(ev.ap);
+    }
+  }
+
+  unlock();
+}