tabs and tab overview

log.c

@@ -0,0 +1,231 @@
+#include "log.h"
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+#include <unistd.h>
+
+#include "debug.h"
+#include "util.h"
+#include "xsnprintf.h"
+
+static bool colorize = false;
+static bool do_syslog = false;
+static enum log_class log_level = LOG_CLASS_NONE;
+
+static const struct {
+    const char name[8];
+    const char log_prefix[7];
+    uint8_t color;
+    int syslog_equivalent;
+} log_level_map[] = {
+    [LOG_CLASS_NONE] = {"none", "none", 5, -1},
+    [LOG_CLASS_ERROR] = {"error", " err", 31, LOG_ERR},
+    [LOG_CLASS_WARNING] = {"warning", "warn", 33, LOG_WARNING},
+    [LOG_CLASS_INFO] = {"info", "info", 97, LOG_INFO},
+    [LOG_CLASS_DEBUG] = {"debug", " dbg", 36, LOG_DEBUG},
+};
+
+void
+log_init(enum log_colorize _colorize, bool _do_syslog,
+         enum log_facility syslog_facility, enum log_class _log_level)
+{
+    static const int facility_map[] = {
+        [LOG_FACILITY_USER] = LOG_USER,
+        [LOG_FACILITY_DAEMON] = LOG_DAEMON,
+    };
+
+    /* Don't use colors if NO_COLOR is defined and not empty */
+    const char *no_color_str = getenv("NO_COLOR");
+    const bool no_color = no_color_str != NULL && no_color_str[0] != '\0';
+
+    colorize = _colorize == LOG_COLORIZE_ALWAYS
+               || (_colorize == LOG_COLORIZE_AUTO
+                   && !no_color && isatty(STDERR_FILENO));
+    do_syslog = _do_syslog;
+    log_level = _log_level;
+
+    int slvl = log_level_map[_log_level].syslog_equivalent;
+    if (slvl < 0)
+        do_syslog = false;
+
+    if (do_syslog) {
+        openlog(NULL, /*LOG_PID*/0, facility_map[syslog_facility]);
+
+        xassert(slvl >= 0);
+        setlogmask(LOG_UPTO(slvl));
+    }
+}
+
+void
+log_deinit(void)
+{
+    if (do_syslog)
+        closelog();
+}
+
+static void
+_log(enum log_class log_class, const char *module, const char *file, int lineno,
+     const char *fmt, int sys_errno, va_list va)
+{
+    xassert(log_class > LOG_CLASS_NONE);
+    xassert(log_class < ALEN(log_level_map));
+
+    if (log_class > log_level)
+        return;
+
+    const char *prefix = log_level_map[log_class].log_prefix;
+    unsigned int class_clr = log_level_map[log_class].color;
+
+    char clr[16];
+    xsnprintf(clr, sizeof(clr), "\033[%um", class_clr);
+    fprintf(stderr, "%s%s%s: ", colorize ? clr : "", prefix, colorize ? "\033[0m" : "");
+
+    if (colorize)
+        fputs("\033[2m", stderr);
+    fprintf(stderr, "%s:%d: ", file, lineno);
+    if (colorize)
+        fputs("\033[0m", stderr);
+
+    vfprintf(stderr, fmt, va);
+
+    if (sys_errno != 0)
+        fprintf(stderr, ": %s", strerror(sys_errno));
+
+    fputc('\n', stderr);
+}
+
+static void
+_sys_log(enum log_class log_class, const char *module,
+         const char UNUSED *file, int UNUSED lineno,
+         const char *fmt, int sys_errno, va_list va)
+{
+    xassert(log_class > LOG_CLASS_NONE);
+    xassert(log_class < ALEN(log_level_map));
+
+    if (!do_syslog)
+        return;
+
+    if (log_class > log_level)
+        return;
+
+    /* Map our log level to syslog's level */
+    int level = log_level_map[log_class].syslog_equivalent;
+
+    char msg[4096];
+    int n = vsnprintf(msg, sizeof(msg), fmt, va);
+    xassert(n >= 0);
+
+    if (sys_errno != 0 && (size_t)n < sizeof(msg))
+        snprintf(msg + n, sizeof(msg) - n, ": %s", strerror(sys_errno));
+
+    syslog(level, "%s: %s", module, msg);
+}
+
+void
+log_msg_va(enum log_class log_class, const char *module,
+           const char *file, int lineno, const char *fmt, va_list va)
+{
+    va_list va2;
+    va_copy(va2, va);
+    _log(log_class, module, file, lineno, fmt, 0, va);
+    _sys_log(log_class, module, file, lineno, fmt, 0, va2);
+    va_end(va2);
+}
+
+void
+log_msg(enum log_class log_class, const char *module,
+        const char *file, int lineno, const char *fmt, ...)
+{
+    va_list va;
+    va_start(va, fmt);
+    log_msg_va(log_class, module, file, lineno, fmt, va);
+    va_end(va);
+}
+
+void
+log_errno_va(enum log_class log_class, const char *module,
+             const char *file, int lineno,
+             const char *fmt, va_list va)
+{
+    log_errno_provided_va(log_class, module, file, lineno, errno, fmt, va);
+}
+
+void
+log_errno(enum log_class log_class, const char *module,
+          const char *file, int lineno,
+          const char *fmt, ...)
+{
+    va_list va;
+    va_start(va, fmt);
+    log_errno_va(log_class, module, file, lineno, fmt, va);
+    va_end(va);
+}
+
+void
+log_errno_provided_va(enum log_class log_class, const char *module,
+                      const char *file, int lineno, int errno_copy,
+                      const char *fmt, va_list va)
+{
+    va_list va2;
+    va_copy(va2, va);
+    _log(log_class, module, file, lineno, fmt, errno_copy, va);
+    _sys_log(log_class, module, file, lineno, fmt, errno_copy, va2);
+    va_end(va2);
+}
+
+void
+log_errno_provided(enum log_class log_class, const char *module,
+                   const char *file, int lineno, int errno_copy,
+                   const char *fmt, ...)
+{
+    va_list va;
+    va_start(va, fmt);
+    log_errno_provided_va(log_class, module, file, lineno, errno_copy, fmt, va);
+    va_end(va);
+}
+
+static size_t
+map_len(void)
+{
+    size_t len = ALEN(log_level_map);
+#ifndef _DEBUG
+    /* Exclude "debug" entry for non-debug builds */
+    len--;
+#endif
+    return len;
+}
+
+int
+log_level_from_string(const char *str)
+{
+    if (unlikely(str[0] == '\0'))
+        return -1;
+
+    for (int i = 0, n = map_len(); i < n; i++)
+        if (streq(str, log_level_map[i].name))
+            return i;
+
+    return -1;
+}
+
+const char *
+log_level_string_hint(void)
+{
+    static char buf[64];
+    if (buf[0] != '\0')
+        return buf;
+
+    for (size_t i = 0, pos = 0, n = map_len(); i < n; i++) {
+        const char *entry = log_level_map[i].name;
+        const char *delim = (i + 1 < n) ? ", " : "";
+        pos += xsnprintf(buf + pos, sizeof(buf) - pos, "'%s'%s", entry, delim);
+    }
+
+    return buf;
+}