Make shell command and its option rc file options instead of hardcode…

…d strings.

This allows users to modify the shell command that execute "editors".
Two new options appear in rc file:
- shell.path (default to "/bin/sh")
- shell.options (default to "-c")

These options can only be changed from the rc file, not at runtime.
Tests are made to check that shell.path is not empty and lead to
an executable file.

src/editors.c

@@ -27,8 +27,6 @@
 #define EDITOR_WINDOW_WIDTH 500
 #define EDITOR_WINDOW_HEIGHT 300
 
-#define COMMAND_SHELL "/bin/sh"
-#define COMMAND_OPT  "-c"
 
 
 typedef struct _EditorVerboseData EditorVerboseData;
@@ -577,16 +575,32 @@ static gint editor_command_one(const gchar *template, GList *list, EditorData *e
 
 	ok = !(ed->flags & EDITOR_ERROR_MASK);
 
+	if (ok)
+		{
+		ok = (options->shell.path && *options->shell.path);
+		if (!ok) log_printf("ERROR: empty shell command\n");
+
+		if (ok)
+			{
+			ok = (access(options->shell.path, X_OK) == 0);
+			if (!ok) log_printf("ERROR: cannot execute shell command '%s'\n", options->shell.path);
+			}
+
+		if (!ok) ed->flags |= EDITOR_ERROR_CANT_EXEC;
+		}
+
 	if (ok)
 		{
 		gchar *working_directory;
 		gchar *args[4];
+		guint n = 0;
 
 		working_directory = remove_level_from_path(fd->path);
-		args[0] = COMMAND_SHELL;
-		args[1] = COMMAND_OPT;
-		args[2] = command;
-		args[3] = NULL;
+		args[n++] = options->shell.path;
+		if (options->shell.options && *options->shell.options)
+			args[n++] = options->shell.options;
+		args[n++] = command;
+		args[n] = NULL;
 
 		ok = g_spawn_async_with_pipes(working_directory, args, NULL,
 				      G_SPAWN_DO_NOT_REAP_CHILD, /* GSpawnFlags */

src/main.c

@@ -580,6 +580,9 @@ static void setup_default_options(void)
 	sidecar_ext_add_defaults();
 	options->layout.order = g_strdup("123");
 	options->properties.tabs_order = g_strdup(info_tab_default_order());
+
+	options->shell.path = g_strdup(GQ_DEFAULT_SHELL_PATH);
+	options->shell.options = g_strdup(GQ_DEFAULT_SHELL_OPTIONS);
 }
 
 static void exit_program_final(void)

src/main.h

@@ -90,6 +90,9 @@
 
 #define GQ_EDITOR_GENERIC_SLOTS 10
 
+#define GQ_DEFAULT_SHELL_PATH "/bin/sh"
+#define GQ_DEFAULT_SHELL_OPTIONS "-c"
+
 #define COLOR_PROFILE_INPUTS 4
 
 #define DEFAULT_THUMB_WIDTH	96

src/options.h

@@ -110,6 +110,12 @@ struct _ConfOptions
 	/* editors */
 	Editor editor[GQ_EDITOR_SLOTS];
 
+	/* shell */
+	struct {
+		gchar *path;
+		gchar *options;
+	} shell;
+
 	/* file sorting */
 	struct {
 		SortType method;

src/rcfile.c

@@ -548,6 +548,12 @@ void save_options(void)
 	WRITE_INT(color_profile.screen_type);
 	WRITE_CHAR(color_profile.screen_file);
 
+
+	WRITE_SUBTITLE("Shell command");
+	WRITE_CHAR(shell.path);
+	WRITE_CHAR(shell.options);
+
+
 	WRITE_SUBTITLE("External Programs");
 	secure_fprintf(ssi, "# Maximum of %d programs (external_1 through external_%d)\n", GQ_EDITOR_GENERIC_SLOTS, GQ_EDITOR_GENERIC_SLOTS);
 	secure_fprintf(ssi, "# external_%d through external_%d are used for file ops\n", GQ_EDITOR_GENERIC_SLOTS + 1, GQ_EDITOR_SLOTS);
@@ -879,6 +885,10 @@ void load_options(void)
 		READ_INT(color_profile.screen_type);
 		READ_CHAR(color_profile.screen_file);
 
+		/* Shell command */
+		READ_CHAR(shell.path);
+		READ_CHAR(shell.options);
+
 		/* External Programs */
 
 		if (is_numbered_option(option, "external_", &i))