Add --pause-on-exit

Add an option to make scrcpy pause on exit.

Three behaviors are possible:
 - always pause on exit:
    --pause-on-exit
    --pause-on-exit=true
 - never pause on exit:
    (no option)
    --pause-on-exit=false
 - pause when scrcpy returns with an error (a non-zero exit code):
    --pause-on-exit=if-error

This is useful to prevent the terminal window from automatically
closing, so that error messages can be read.

Refs #3817 <#3817>
Refs #3822 <#3822>
PR #4130 <#4130>

app/data/bash-completion/scrcpy

@@ -44,6 +44,8 @@ _scrcpy() {
         --no-video-playback
         --otg
         -p --port=
+        --pause-on-exit
+        --pause-on-exit=
         --power-off-on-close
         --prefer-text
         --print-fps
@@ -97,6 +99,10 @@ _scrcpy() {
             COMPREPLY=($(compgen -W 'unlocked initial 0 1 2 3' -- "$cur"))
             return
             ;;
+        --pause-on-exit)
+            COMPREPLY=($(compgen -W 'true false if-error' -- "$cur"))
+            return
+            ;;
         -r|--record)
             COMPREPLY=($(compgen -f -- "$cur"))
             return

app/data/zsh-completion/_scrcpy

@@ -50,6 +50,7 @@ arguments=(
     '--no-video-playback[Disable video playback]'
     '--otg[Run in OTG mode \(simulating physical keyboard and mouse\)]'
     {-p,--port=}'[\[port\[\:port\]\] Set the TCP port \(range\) used by the client to listen]'
+    '--pause-on-exit=[Make scrcpy pause before exiting]:mode:(true false if-error)'
     '--power-off-on-close[Turn the device screen off when closing scrcpy]'
     '--prefer-text[Inject alpha characters and space as text events instead of key events]'
     '--print-fps[Start FPS counter, to print frame logs to the console]'

app/scrcpy.1

@@ -267,6 +267,16 @@ Set the TCP port (range) used by the client to listen.
 
 Default is 27183:27199.
 
+.TP
+\fB\-\-pause\-on\-exit\fR[=\fImode\fR]
+Configure pause on exit. Possible values are "true" (always pause on exit), "false" (never pause on exit) and "if-error" (pause only if an error occured).
+
+This is useful to prevent the terminal window from automatically closing, so that error messages can be read.
+
+Default is "false".
+
+Passing the option without argument is equivalent to passing "true".
+
 .TP
 .B \-\-power\-off\-on\-close
 Turn the device screen off when closing scrcpy.

app/src/cli.c

@@ -79,6 +79,7 @@ enum {
     OPT_AUDIO_SOURCE,
     OPT_KILL_ADB_ON_CLOSE,
     OPT_TIME_LIMIT,
+    OPT_PAUSE_ON_EXIT,
 };
 
 struct sc_option {
@@ -463,6 +464,20 @@ static const struct sc_option options[] = {
                 "Default is " STR(DEFAULT_LOCAL_PORT_RANGE_FIRST) ":"
                               STR(DEFAULT_LOCAL_PORT_RANGE_LAST) ".",
     },
+    {
+        .longopt_id = OPT_PAUSE_ON_EXIT,
+        .longopt = "pause-on-exit",
+        .argdesc = "mode",
+        .optional_arg = true,
+        .text = "Configure pause on exit. Possible values are \"true\" (always "
+                "pause on exit), \"false\" (never pause on exit) and "
+                "\"if-error\" (pause only if an error occured).\n"
+                "This is useful to prevent the terminal window from "
+                "automatically closing, so that error messages can be read.\n"
+                "Default is \"false\".\n"
+                "Passing the option without argument is equivalent to passing "
+                "\"true\".",
+    },
     {
         .longopt_id = OPT_POWER_OFF_ON_CLOSE,
         .longopt = "power-off-on-close",
@@ -1637,6 +1652,29 @@ parse_time_limit(const char *s, sc_tick *tick) {
     return true;
 }
 
+static bool
+parse_pause_on_exit(const char *s, enum sc_pause_on_exit *pause_on_exit) {
+    if (!s || !strcmp(s, "true")) {
+        *pause_on_exit = SC_PAUSE_ON_EXIT_TRUE;
+        return true;
+    }
+
+    if (!strcmp(s, "false")) {
+        *pause_on_exit = SC_PAUSE_ON_EXIT_FALSE;
+        return true;
+    }
+
+    if (!strcmp(s, "if-error")) {
+        *pause_on_exit = SC_PAUSE_ON_EXIT_IF_ERROR;
+        return true;
+    }
+
+    LOGE("Unsupported pause on exit mode: %s "
+         "(expected true, false or if-error)", optarg);
+    return false;
+
+}
+
 static bool
 parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                        const char *optstring, const struct option *longopts) {
@@ -1977,6 +2015,11 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
                     return false;
                 }
                 break;
+            case OPT_PAUSE_ON_EXIT:
+                if (!parse_pause_on_exit(optarg, &args->pause_on_exit)) {
+                    return false;
+                }
+                break;
             default:
                 // getopt prints the error message on stderr
                 return false;
@@ -2190,6 +2233,37 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
     return true;
 }
 
+static enum sc_pause_on_exit
+sc_get_pause_on_exit(int argc, char *argv[]) {
+    // Read arguments backwards so that the last --pause-on-exit is considered
+    // (same behavior as getopt())
+    for (int i = argc - 1; i >= 1; --i) {
+        const char *arg = argv[i];
+        // Starts with "--pause-on-exit"
+        if (!strncmp("--pause-on-exit", arg, 15)) {
+            if (arg[15] == '\0') {
+                // No argument
+                return SC_PAUSE_ON_EXIT_TRUE;
+            }
+            if (arg[15] != '=') {
+                // Invalid parameter, ignore
+                return SC_PAUSE_ON_EXIT_FALSE;
+            }
+            const char *value = &arg[16];
+            if (!strcmp(value, "true")) {
+                return SC_PAUSE_ON_EXIT_TRUE;
+            }
+            if (!strcmp(value, "if-error")) {
+                return SC_PAUSE_ON_EXIT_IF_ERROR;
+            }
+            // Set to false, inclusing when the value is invalid
+            return SC_PAUSE_ON_EXIT_FALSE;
+        }
+    }
+
+    return false;
+}
+
 bool
 scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
     struct sc_getopt_adapter adapter;
@@ -2203,5 +2277,11 @@ scrcpy_parse_args(struct scrcpy_cli_args *args, int argc, char *argv[]) {
 
     sc_getopt_adapter_destroy(&adapter);
 
+    if (!ret && args->pause_on_exit == SC_PAUSE_ON_EXIT_FALSE) {
+        // Check if "--pause-on-exit" is present in the arguments list, because
+        // it must be taken into account even if command line parsing failed
+        args->pause_on_exit = sc_get_pause_on_exit(argc, argv);
+    }
+
     return ret;
 }

app/src/cli.h

@@ -7,10 +7,17 @@
 
 #include "options.h"
 
+enum sc_pause_on_exit {
+    SC_PAUSE_ON_EXIT_TRUE,
+    SC_PAUSE_ON_EXIT_FALSE,
+    SC_PAUSE_ON_EXIT_IF_ERROR,
+};
+
 struct scrcpy_cli_args {
     struct scrcpy_options opts;
     bool help;
     bool version;
+    enum sc_pause_on_exit pause_on_exit;
 };
 
 void

app/src/main.c

@@ -39,26 +39,32 @@ main_scrcpy(int argc, char *argv[]) {
         .opts = scrcpy_options_default,
         .help = false,
         .version = false,
+        .pause_on_exit = SC_PAUSE_ON_EXIT_FALSE,
     };
 
 #ifndef NDEBUG
     args.opts.log_level = SC_LOG_LEVEL_DEBUG;
 #endif
 
+    enum scrcpy_exit_code ret;
+
     if (!scrcpy_parse_args(&args, argc, argv)) {
-        return SCRCPY_EXIT_FAILURE;
+        ret = SCRCPY_EXIT_FAILURE;
+        goto end;
     }
 
     sc_set_log_level(args.opts.log_level);
 
     if (args.help) {
         scrcpy_print_usage(argv[0]);
-        return SCRCPY_EXIT_SUCCESS;
+        ret = SCRCPY_EXIT_SUCCESS;
+        goto end;
     }
 
     if (args.version) {
         scrcpy_print_version();
-        return SCRCPY_EXIT_SUCCESS;
+        ret = SCRCPY_EXIT_SUCCESS;
+        goto end;
     }
 
 #ifdef SCRCPY_LAVF_REQUIRES_REGISTER_ALL
@@ -72,18 +78,26 @@ main_scrcpy(int argc, char *argv[]) {
 #endif
 
     if (!net_init()) {
-        return SCRCPY_EXIT_FAILURE;
+        ret = SCRCPY_EXIT_FAILURE;
+        goto end;
     }
 
     sc_log_configure();
 
 #ifdef HAVE_USB
-    enum scrcpy_exit_code ret = args.opts.otg ? scrcpy_otg(&args.opts)
-                                              : scrcpy(&args.opts);
+    ret = args.opts.otg ? scrcpy_otg(&args.opts) : scrcpy(&args.opts);
 #else
-    enum scrcpy_exit_code ret = scrcpy(&args.opts);
+    ret = scrcpy(&args.opts);
 #endif
 
+end:
+    if (args.pause_on_exit == SC_PAUSE_ON_EXIT_TRUE ||
+            (args.pause_on_exit == SC_PAUSE_ON_EXIT_IF_ERROR &&
+                ret != SCRCPY_EXIT_SUCCESS)) {
+        printf("Press Enter to continue...\n");
+        getchar();
+    }
+
     return ret;
 }