Add --log-level option

Now the log level can be set with:

    casync --log-level debug|info|error ...

This command-line argument overrides the environment variable
`CASYNC_LOG_LEVEL`.

Closes: #185
Signed-off-by: Arnaud Rebillout <[email protected]>

Author: elboulangero

doc/casync.rst

@@ -151,6 +151,7 @@ Options
 General options:
 
 --help, -h                      Show terse help output
+--log-level=<LEVEL>, -l         Set log level (debug, info, err)
 --verbose, -v                   Show terse status information during runtime
 --dry-run, -n                   Only print what would be removed with **gc**
 --store=PATH                    The primary chunk store to use

src/casync-tool.c

@@ -43,6 +43,7 @@ static enum arg_what {
         WHAT_DIRECTORY,
         _WHAT_INVALID = -1,
 } arg_what = _WHAT_INVALID;
+static int arg_log_level = -1;
 static bool arg_verbose = false;
 static bool arg_dry_run = false;
 static bool arg_exclude_nodump = true;
@@ -88,6 +89,7 @@ static void help(void) {
                "Content-Addressable Data Synchronization Tool\n\n"
                "  -h --help                  Show this help\n"
                "     --version               Show brief version information\n"
+               "  -l --log-level=LEVEL       Set log level (debug, info, err)\n"
                "  -v --verbose               Show terse status information during runtime\n"
                "  -n --dry-run               When garbage collecting, only print what would\n"
                "                             be done\n"
@@ -349,6 +351,7 @@ static int parse_argv(int argc, char *argv[]) {
         static const struct option options[] = {
                 { "help",              no_argument,       NULL, 'h'                   },
                 { "version",           no_argument,       NULL, ARG_VERSION           },
+                { "log-level",         required_argument, NULL, 'l'                   },
                 { "verbose",           no_argument,       NULL, 'v'                   },
                 { "dry-run",           no_argument,       NULL, 'n'                   },
                 { "store",             required_argument, NULL, ARG_STORE             },
@@ -387,7 +390,7 @@ static int parse_argv(int argc, char *argv[]) {
         if (getenv_bool("CASYNC_VERBOSE") > 0)
                 arg_verbose = true;
 
-        while ((c = getopt_long(argc, argv, "hvnc", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "hl:vnc", options, NULL)) >= 0) {
 
                 switch (c) {
 
@@ -399,6 +402,15 @@ static int parse_argv(int argc, char *argv[]) {
                         version();
                         return 0;
 
+                case 'l':
+                        r = set_log_level_from_string(optarg);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to parse log level \"%s\": %m", optarg);
+
+                        arg_log_level = r;
+
+                        break;
+
                 case 'v':
                         arg_verbose = true;
                         break;
@@ -679,7 +691,13 @@ static int parse_argv(int argc, char *argv[]) {
                 }
         }
 
-        /* Propagate our verbose setting to helpers we fork off */
+        /* Propagate some settings to helpers we fork off */
+        if (arg_log_level >= 0) {
+                char buffer[DECIMAL_STR_MAX(int)];
+                snprintf(buffer, sizeof(buffer), "%d", arg_log_level);
+                (void) setenv("CASYNC_LOG_LEVEL", buffer, 1);
+        }
+
         if (arg_verbose)
                 (void) putenv((char*) "CASYNC_VERBOSE=1");
         else

src/log.c

@@ -10,29 +10,36 @@
 
 static int cached_log_level = -1;
 
+static int level_from_string(const char *str) {
+        if (STR_IN_SET(str, "emerg", "emergency", "0"))
+                return LOG_EMERG;
+        else if (STR_IN_SET(str, "alert", "1"))
+                return LOG_ALERT;
+        else if (STR_IN_SET(str, "crit", "critical", "2"))
+                return LOG_CRIT;
+        else if (STR_IN_SET(str, "err", "error", "3"))
+                return LOG_ERR;
+        else if (STR_IN_SET(str, "warn", "warning", "4"))
+                return LOG_WARNING;
+        else if (STR_IN_SET(str, "notice", "5"))
+                return LOG_NOTICE;
+        else if (STR_IN_SET(str, "info", "6"))
+                return LOG_INFO;
+        else if (STR_IN_SET(str, "debug", "7"))
+                return LOG_DEBUG;
+        else
+                return -EINVAL;
+}
+
 static int get_log_level(void) {
         if (cached_log_level < 0) {
                 const char *e;
 
                 cached_log_level = LOG_INFO;
 
                 e = getenv("CASYNC_LOG_LEVEL");
-                if (e) {
-                        if (STR_IN_SET(e, "emerg", "emergency", "0"))
-                                cached_log_level = LOG_EMERG;
-                        else if (STR_IN_SET(e, "alert", "1"))
-                                cached_log_level = LOG_ALERT;
-                        else if (STR_IN_SET(e, "crit", "critical", "2"))
-                                cached_log_level = LOG_CRIT;
-                        else if (STR_IN_SET(e, "err", "error", "3"))
-                                cached_log_level = LOG_ERR;
-                        else if (STR_IN_SET(e, "warn", "warning", "4"))
-                                cached_log_level = LOG_WARNING;
-                        else if (STR_IN_SET(e, "notice", "5"))
-                                cached_log_level = LOG_NOTICE;
-                        else if (STR_IN_SET(e, "debug", "7"))
-                                cached_log_level = LOG_DEBUG;
-                }
+                if (e)
+                        set_log_level_from_string(e);
         }
 
         return cached_log_level;
@@ -42,6 +49,17 @@ void set_log_level(int level) {
         cached_log_level = level;
 }
 
+int set_log_level_from_string(const char *str) {
+        int level;
+
+        level = level_from_string(str);
+        if (level < 0)
+                return level;
+
+        cached_log_level = level;
+        return level;
+}
+
 static int log_fullv(
                 int level,
                 int error,

src/log.h

@@ -38,3 +38,4 @@ static inline int log_oom(void) {
         } while(false)
 
 void set_log_level(int level);
+int set_log_level_from_string(const char *str);