Add cli option to set the verbosity level

The verbosity was set either to info (in release mode) or debug (in
debug mode).

Add a command-line argument to change it, so that users can enable debug
logs using the release:

    scrcpy -Vdebug

app/scrcpy.1

@@ -154,6 +154,12 @@ It only shows physical touches (not clicks from scrcpy).
 .B \-v, \-\-version
 Print the version of scrcpy.
 
+.TP
+.BI "\-V, \-\-verbosity " value
+Set the log level ("debug", "info", "warn" or "error").
+
+Default is "info" for release builds, "debug" for debug builds.
+
 .TP
 .B \-w, \-\-stay-awake
 Keep the device on while scrcpy is running.

app/src/cli.c

@@ -145,6 +145,14 @@ scrcpy_print_usage(const char *arg0) {
         "\n"
         "    -v, --version\n"
         "        Print the version of scrcpy.\n"
+        "\n"
+        "    -V, --verbosity value\n"
+        "        Set the log level (debug, info, warn or error).\n"
+#ifndef NDEBUG
+        "        Default is debug.\n"
+#else
+        "        Default is info.\n"
+#endif
         "\n"
         "    -w, --stay-awake\n"
         "        Keep the device on while scrcpy is running.\n"
@@ -433,6 +441,32 @@ parse_display_id(const char *s, uint16_t *display_id) {
     return true;
 }
 
+static bool
+parse_log_level(const char *s, enum sc_log_level *log_level) {
+    if (!strcmp(s, "debug")) {
+        *log_level = SC_LOG_LEVEL_DEBUG;
+        return true;
+    }
+
+    if (!strcmp(s, "info")) {
+        *log_level = SC_LOG_LEVEL_INFO;
+        return true;
+    }
+
+    if (!strcmp(s, "warn")) {
+        *log_level = SC_LOG_LEVEL_WARN;
+        return true;
+    }
+
+    if (!strcmp(s, "error")) {
+        *log_level = SC_LOG_LEVEL_ERROR;
+        return true;
+    }
+
+    LOGE("Could not parse log level: %s", s);
+    return false;
+}
+
 static bool
 parse_record_format(const char *optarg, enum recorder_format *format) {
     if (!strcmp(optarg, "mp4")) {
@@ -513,6 +547,7 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
         {"show-touches",           no_argument,       NULL, 't'},
         {"stay-awake",             no_argument,       NULL, 'w'},
         {"turn-screen-off",        no_argument,       NULL, 'S'},
+        {"verbosity",              required_argument, NULL, 'V'},
         {"version",                no_argument,       NULL, 'v'},
         {"window-title",           required_argument, NULL, OPT_WINDOW_TITLE},
         {"window-x",               required_argument, NULL, OPT_WINDOW_X},
@@ -529,8 +564,8 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
     optind = 0; // reset to start from the first argument in tests
 
     int c;
-    while ((c = getopt_long(argc, argv, "b:c:fF:hm:nNp:r:s:StTvw", long_options,
+    while ((c = getopt_long(argc, argv, "b:c:fF:hm:nNp:r:s:StTvV:w",
-                            NULL)) != -1) {
+                            long_options, NULL)) != -1) {
         switch (c) {
             case 'b':
                 if (!parse_bit_rate(optarg, &opts->bit_rate)) {
@@ -609,6 +644,11 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
             case 'v':
                 args->version = true;
                 break;
+            case 'V':
+                if (!parse_log_level(optarg, &opts->log_level)) {
+                    return false;
+                }
+                break;
             case 'w':
                 opts->stay_awake = true;
                 break;

app/src/main.c

@@ -29,6 +29,24 @@ print_version(void) {
                                                LIBAVUTIL_VERSION_MICRO);
 }
 
+static SDL_LogPriority
+convert_log_level_to_sdl(enum sc_log_level level) {
+    switch (level) {
+        case SC_LOG_LEVEL_DEBUG:
+            return SDL_LOG_PRIORITY_DEBUG;
+        case SC_LOG_LEVEL_INFO:
+            return SDL_LOG_PRIORITY_INFO;
+        case SC_LOG_LEVEL_WARN:
+            return SDL_LOG_PRIORITY_WARN;
+        case SC_LOG_LEVEL_ERROR:
+            return SDL_LOG_PRIORITY_ERROR;
+        default:
+            assert(!"unexpected log level");
+            return SC_LOG_LEVEL_INFO;
+    }
+}
+
+
 int
 main(int argc, char *argv[]) {
 #ifdef __WINDOWS__
@@ -38,20 +56,23 @@ main(int argc, char *argv[]) {
     setbuf(stderr, NULL);
 #endif
 
-#ifndef NDEBUG
-    SDL_LogSetAllPriority(SDL_LOG_PRIORITY_DEBUG);
-#endif
-
     struct scrcpy_cli_args args = {
         .opts = SCRCPY_OPTIONS_DEFAULT,
         .help = false,
         .version = false,
     };
 
+#ifndef NDEBUG
+    args.opts.log_level = SC_LOG_LEVEL_DEBUG;
+#endif
+
     if (!scrcpy_parse_args(&args, argc, argv)) {
         return 1;
     }
 
+    SDL_LogPriority sdl_log = convert_log_level_to_sdl(args.opts.log_level);
+    SDL_LogSetAllPriority(sdl_log);
+
     if (args.help) {
         scrcpy_print_usage(argv[0]);
         return 0;

app/src/scrcpy.c

@@ -293,6 +293,7 @@ bool
 scrcpy(const struct scrcpy_options *options) {
     bool record = !!options->record_filename;
     struct server_params params = {
+        .log_level = options->log_level,
         .crop = options->crop,
         .port_range = options->port_range,
         .max_size = options->max_size,

app/src/scrcpy.h

@@ -8,6 +8,7 @@
 #include "common.h"
 #include "input_manager.h"
 #include "recorder.h"
+#include "util/log.h"
 
 struct scrcpy_options {
     const char *serial;
@@ -17,6 +18,7 @@ struct scrcpy_options {
     const char *push_target;
     const char *render_driver;
     const char *codec_options;
+    enum sc_log_level log_level;
     enum recorder_format record_format;
     struct port_range port_range;
     uint16_t max_size;
@@ -50,6 +52,7 @@ struct scrcpy_options {
     .push_target = NULL, \
     .render_driver = NULL, \
     .codec_options = NULL, \
+    .log_level = SC_LOG_LEVEL_INFO, \
     .record_format = RECORDER_FORMAT_AUTO, \
     .port_range = { \
         .first = DEFAULT_LOCAL_PORT_RANGE_FIRST, \

app/src/server.c

@@ -229,6 +229,23 @@ enable_tunnel_any_port(struct server *server, struct port_range port_range) {
     return enable_tunnel_forward_any_port(server, port_range);
 }
 
+static const char *
+log_level_to_server_string(enum sc_log_level level) {
+    switch (level) {
+        case SC_LOG_LEVEL_DEBUG:
+            return "debug";
+        case SC_LOG_LEVEL_INFO:
+            return "info";
+        case SC_LOG_LEVEL_WARN:
+            return "warn";
+        case SC_LOG_LEVEL_ERROR:
+            return "error";
+        default:
+            assert(!"unexpected log level");
+            return "(unknown)";
+    }
+}
+
 static process_t
 execute_server(struct server *server, const struct server_params *params) {
     char max_size_string[6];
@@ -259,11 +276,7 @@ execute_server(struct server *server, const struct server_params *params) {
         "/", // unused
         "com.genymobile.scrcpy.Server",
         SCRCPY_VERSION,
-#ifndef NDEBUG
+        log_level_to_server_string(params->log_level),
-        "debug",
-#else
-        "info",
-#endif
         max_size_string,
         bit_rate_string,
         max_fps_string,

app/src/server.h

@@ -9,6 +9,7 @@
 #include "config.h"
 #include "command.h"
 #include "common.h"
+#include "util/log.h"
 #include "util/net.h"
 
 struct server {
@@ -43,6 +44,7 @@ struct server {
 }
 
 struct server_params {
+    enum sc_log_level log_level;
     const char *crop;
     const char *codec_options;
     struct port_range port_range;

app/src/util/log.h

@@ -3,6 +3,13 @@
 
 #include <SDL2/SDL_log.h>
 
+enum sc_log_level {
+    SC_LOG_LEVEL_DEBUG,
+    SC_LOG_LEVEL_INFO,
+    SC_LOG_LEVEL_WARN,
+    SC_LOG_LEVEL_ERROR,
+};
+
 #define LOGV(...) SDL_LogVerbose(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)
 #define LOGD(...) SDL_LogDebug(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)
 #define LOGI(...) SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION, __VA_ARGS__)