nixos fix: look for gsr-kms-server in PATH if not found in same directory as gpu-screen-recorder

kms/client/kms_client.c

@@ -183,6 +183,40 @@ static void file_get_directory(char *filepath) {
         *end = '\0';
 }
 
+static bool find_program_in_path(const char *program_name, char *filepath, int filepath_len) {
+    const char *path = getenv("PATH");
+    if(!path)
+        return false;
+
+    int program_name_len = strlen(program_name);
+    const char *end = path + strlen(path);
+    while(path != end) {
+        const char *part_end = strchr(path, ':');
+        const char *next = part_end;
+        if(part_end) {
+            next = part_end + 1;
+        } else {
+            part_end = end;
+            next = end;
+        }
+
+        int len = part_end - path;
+        if(len + 1 + program_name_len < filepath_len) {
+            memcpy(filepath, path, len);
+            filepath[len] = '/';
+            memcpy(filepath + len + 1, program_name, program_name_len);
+            filepath[len + 1 + program_name_len] = '\0';
+
+            if(access(filepath, F_OK) == 0)
+                return true;
+        }
+
+        path = next;
+    }
+
+    return false;
+}
+
 int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
     int result = -1;
     self->kms_server_pid = -1;
@@ -212,8 +246,11 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
     }
 
     if(access(server_filepath, F_OK) != 0) {
-        fprintf(stderr, "gsr error: gsr_kms_client_init: gsr-kms-server is not installed (%s not found)\n", server_filepath);
+        fprintf(stderr, "gsr info: gsr_kms_client_init: gsr-kms-server is not installed in the same directory as gpu-screen-recorder (%s not found), looking for gsr-kms-server in PATH instead\n", server_filepath);
-        return -1;
+        if(!find_program_in_path("gsr-kms-server", server_filepath, sizeof(server_filepath)) || access(server_filepath, F_OK) != 0) {
+            fprintf(stderr, "gsr error: gsr_kms_client_init: gsr-kms-server was not found in PATH. Please install gpu-screen-recorder properly\n");
+            return -1;
+        }
     }
 
     fprintf(stderr, "gsr info: gsr_kms_client_init: setting up connection to %s\n", server_filepath);

src/main.cpp

@@ -1162,7 +1162,7 @@ static void usage_full() {
     fprintf(stderr, "        Note: the directory to the portal session token file is created automatically if it doesn't exist.\n");
     fprintf(stderr, "\n");
     fprintf(stderr, "  -encoder\n");
-    fprintf(stderr, "        Which device should be used for video encoding. Should either be 'gpu' or 'cpu'. Does currently only work with h264 codec option (-k).\n");
+    fprintf(stderr, "        Which device should be used for video encoding. Should either be 'gpu' or 'cpu'. 'cpu' option currently only work with h264 codec option (-k).\n");
     fprintf(stderr, "        Optional, set to 'gpu' by default.\n");
     fprintf(stderr, "\n");
     fprintf(stderr, "  --info\n");
@@ -1177,6 +1177,7 @@ static void usage_full() {
     fprintf(stderr, "        For example:\n");
     fprintf(stderr, "          bluez_input.88:C9:E8:66:A2:27|WH-1000XM4\n");
     fprintf(stderr, "        The <audio_device_name> is the name to pass to GPU Screen Recorder in a -a option.\n");
+    fprintf(stderr, "\n");
     fprintf(stderr, "  --version\n");
     fprintf(stderr, "        Print version (%s) and exit\n", GSR_VERSION);
     fprintf(stderr, "\n");
@@ -1185,7 +1186,7 @@ static void usage_full() {
     fprintf(stderr, "        In replay mode this has to be a directory instead of a file.\n");
     fprintf(stderr, "        Note: the directory to the file is created automatically if it doesn't already exist.\n");
     fprintf(stderr, "\n");
-    fprintf(stderr, "  -v    Prints per second, fps updates. Optional, set to 'yes' by default.\n");
+    fprintf(stderr, "  -v    Prints fps and damage info once per second. Optional, set to 'yes' by default.\n");
     fprintf(stderr, "\n");
     fprintf(stderr, "  -h, --help\n");
     fprintf(stderr, "        Show this help.\n");
@@ -2609,7 +2610,7 @@ int main(int argc, char **argv) {
     setenv("__GL_THREADED_OPTIMIZATIONS", "0", true);
     // Forces low latency encoding mode. Use this environment variable until vaapi supports setting this as a parameter.
     // The downside of this is that it always uses maximum power, which is not ideal for replay mode that runs on system startup.
-    // This option was added in mesa 24.1.4, released on july 17, 2024.
+    // This option was added in mesa 24.1.4, released in july 17, 2024.
     // TODO: Add an option to enable/disable this?
     // Seems like the performance issue is not in encoding, but rendering the frame.
     // Some frames end up taking 10 times longer. Seems to be an issue with amd gpu power management when letting the application sleep on the cpu side?