Adding support for --pre-display-cmd so one can run something like `ls /some/path | wofi --show dmenu --pre-display-cmd 'cat /some/path/%s', and output the original filename, while displaying the contents of the file in the entries

wofi-add-pre-display-cmd.patch

diff -r bae1c99a465f src/main.c
--- a/src/main.c	Mon Feb 22 23:53:57 2021 -0800
+++ b/src/main.c	Fri Oct 22 23:56:28 2021 +0200
@@ -96,6 +96,7 @@
 	printf("--gtk-dark\t-G\tUses the dark variant of the current GTK theme\n");
 	printf("--search\t-Q\tSearch for something immediately on open\n");
 	printf("--monitor\t-o\tSets the monitor to open on\n");
+	printf("--pre-display-cmd\t-r\tRuns command for the displayed entries, without changing the output. %%s for the real string\n");
 	exit(0);
 }
 
@@ -106,7 +107,10 @@
 		ssize_t size = ftell(file);
 		fseek(file, 0, SEEK_SET);
 		char* data = malloc(size + 1);
-		fread(data, 1, size, file);
+		if (fread(data, 1, size, file) != 0) {
+			printf("failed to read stylesheet data from file");
+			exit(EXIT_FAILURE);
+		}
 		fclose(file);
 
 		data[size] = 0;
@@ -422,6 +426,12 @@
 			.val = 'o'
 		},
 		{
+			.name = "pre-display-cmd",
+			.has_arg = required_argument,
+			.flag = NULL,
+			.val = 'r'
+		},
+		{
 			.name = NULL,
 			.has_arg = 0,
 			.flag = NULL,
@@ -457,13 +467,14 @@
 	char* gtk_dark = NULL;
 	char* search = NULL;
 	char* monitor = NULL;
+	char* pre_display_cmd = NULL;
 
 	struct wl_list options;
 	wl_list_init(&options);
 	struct option_node* node;
 
 	int opt;
-	while((opt = getopt_long(argc, argv, "hfc:s:C:dS:W:H:p:x:y:nImk:t:P::ebM:iqvl:aD:L:w:O:GQ:o:", opts, NULL)) != -1) {
+	while((opt = getopt_long(argc, argv, "hfc:s:C:dS:W:H:p:x:y:nImk:t:P::ebM:iqvl:aD:L:w:O:GQ:o:r:", opts, NULL)) != -1) {
 		switch(opt) {
 		case 'h':
 			print_usage(argv);
@@ -572,6 +583,9 @@
 		case 'o':
 			monitor = optarg;
 			break;
+		case 'r':
+			pre_display_cmd = optarg;
+			break;
 		}
 	}
 
@@ -761,6 +775,9 @@
 	if(monitor != NULL) {
 		map_put(config, "monitor", monitor);
 	}
+	if(pre_display_cmd != NULL) {
+		map_put(config, "pre_display_cmd", pre_display_cmd);
+	}
 
 	struct sigaction sigact = {0};
 	sigact.sa_handler = sig;
diff -r bae1c99a465f src/wofi.c
--- a/src/wofi.c	Mon Feb 22 23:53:57 2021 -0800
+++ b/src/wofi.c	Fri Oct 22 23:56:28 2021 +0200
@@ -106,6 +106,7 @@
 static pthread_t mode_thread;
 static bool has_joined_mode = false;
 static char* copy_exec = NULL;
+static char* pre_display_cmd = NULL;
 
 static struct map* keys;
 
@@ -396,10 +397,32 @@
 
 	setup_label(mode, WOFI_PROPERTY_BOX(box));
 
+	char labeltext[1000];
+	if (pre_display_cmd == NULL) {
+		*labeltext = *text;
+	} else {
+		FILE *fp_labeltext;
+		char *cmd_labeltext;
+		if ((asprintf(&cmd_labeltext, pre_display_cmd, text)) == -1) {
+			printf("error parsing pre_display_cmd to run\n");
+			exit(EXIT_FAILURE);
+		}
+		fp_labeltext = popen(cmd_labeltext, "r");
+		if (fp_labeltext == NULL) {
+			printf("error executing '%s'", cmd_labeltext);
+			exit(EXIT_FAILURE);
+		}
+		if (fgets(labeltext, sizeof(labeltext), fp_labeltext) == NULL) {
+			printf("failed to read output of command");
+			exit(EXIT_FAILURE);
+		}
+		pclose(fp_labeltext);
+	}
+
 	if(allow_images) {
-		parse_images(WOFI_PROPERTY_BOX(box), text, true);
+		parse_images(WOFI_PROPERTY_BOX(box), labeltext, true);
 	} else {
-		GtkWidget* label = gtk_label_new(text);
+		GtkWidget* label = gtk_label_new(labeltext);
 		gtk_widget_set_name(label, "text");
 		gtk_label_set_use_markup(GTK_LABEL(label), allow_markup);
 		gtk_label_set_xalign(GTK_LABEL(label), 0);
@@ -536,6 +559,7 @@
 	if(node == NULL) {
 		return FALSE;
 	}
+	char* nodetext = node->text[0];
 
 	GtkWidget* parent;
 	if(node->action_count > 1 && !no_actions) {
@@ -543,7 +567,7 @@
 		g_signal_connect(parent, "activate", G_CALLBACK(expand), NULL);
 		GtkWidget* box;
 		if(node->builder == NULL) {
-			box = create_label(node->mode, node->text[0], node->search_text, node->actions[0]);
+			box = create_label(node->mode, nodetext, node->search_text, node->actions[0]);
 		} else {
 			box = GTK_WIDGET(node->builder->box);
 			setup_label(node->builder->mode->name, WOFI_PROPERTY_BOX(box));
@@ -570,7 +594,7 @@
 		}
 	} else {
 		if(node->builder == NULL) {
-			parent = create_label(node->mode, node->text[0], node->search_text, node->actions[0]);
+			parent = create_label(node->mode, nodetext, node->search_text, node->actions[0]);
 		} else {
 			parent = GTK_WIDGET(node->builder->box);
 			setup_label(node->builder->mode->name, WOFI_PROPERTY_BOX(parent));
@@ -1234,7 +1258,10 @@
 			}
 
 			int fds[2];
-			pipe(fds);
+			if (pipe(fds) == -1) {
+				perror("pipe broken");
+				exit(EXIT_FAILURE);
+			}
 			if(fork() == 0) {
 				close(fds[1]);
 				dup2(fds[0], STDIN_FILENO);
@@ -1244,7 +1271,9 @@
 			}
 			close(fds[0]);
 
-			write(fds[1], action, strlen(action));
+			if (!(write(fds[1], action, strlen(action)) == 0)) {
+				printf("fd pipe failed to write");
+			}
 
 			close(fds[1]);
 
@@ -1674,6 +1703,8 @@
 	char* monitor = map_get(config, "monitor");
 	char* layer = config_get(config, "layer", "top");
 	copy_exec = config_get(config, "copy_exec", "wl-copy");
+	
+	pre_display_cmd = map_get(config, "pre_display_cmd");
 
 	keys = map_init_void();