Alter spawn to return the error message only in error->message

That is, do not cite the original text, program name, or the failed
OS function name (except when the testing program is compiled).
Also cut glib citing of the original text on bad quoting.

src/spawn.c

@@ -74,6 +74,23 @@
 # define DEFAULT_IO_LENGTH 2048
 #else
 # define DEFAULT_IO_LENGTH 4096
+
+/* helper function that cuts glib citing of the original text on bad quoting: it may be long,
+   and only the caller knows whether it's UTF-8. Thought we lose the ' or " failed info. */
+static gboolean spawn_parse_argv(const gchar *command_line, gint *argcp, gchar ***argvp,
+	GError **error)
+{
+	GError *gerror = NULL;
+
+	if (g_shell_parse_argv(command_line, argcp, argvp, &gerror))
+		return TRUE;
+
+	g_set_error_literal(error, gerror->domain, gerror->code,
+		gerror->code == G_SHELL_ERROR_BAD_QUOTING ?
+		_("Text ended before matching quote was found") : gerror->message);
+	g_error_free(gerror);
+	return FALSE;
+}
 #endif
 
 #define G_IO_FAILURE (G_IO_ERR | G_IO_HUP | G_IO_NVAL)  /* always used together */
@@ -104,7 +121,7 @@ static gchar *spawn_get_program_name(const gchar *command_line, GError **error)
 
 	if (!*command_line)
 	{
-		g_set_error(error, G_SHELL_ERROR, G_SHELL_ERROR_EMPTY_STRING,
+		g_set_error_literal(error, G_SHELL_ERROR, G_SHELL_ERROR_EMPTY_STRING,
 			/* TL note: from glib */
 			_("Text was empty (or contained only whitespace)"));
 		return FALSE;
@@ -119,16 +136,14 @@ static gchar *spawn_get_program_name(const gchar *command_line, GError **error)
 		/* Windows allows "foo.exe, but we may have extra arguments */
 		if ((s = strchr(command_line, '"')) == NULL)
 		{
-			g_set_error(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
-				/* TL note: from glib */
-				_("Text ended before matching quote was found for %c."
-				  " (The text was '%s')"), '"', command_line);
+			g_set_error_literal(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
+				_("Text ended before matching quote was found"));
 			return FALSE;
 		}
 
 		if (!strchr(" \t", s[1]))  /* strchr() catches s[1] == '\0' */
 		{
-			g_set_error(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
+			g_set_error_literal(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
 				_("A quoted Windows program name must be entirely inside the quotes"));
 			return FALSE;
 		}
@@ -142,7 +157,7 @@ static gchar *spawn_get_program_name(const gchar *command_line, GError **error)
 
 		if (quote && quote < s)
 		{
-			g_set_error(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
+			g_set_error_literal(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
 				_("A quoted Windows program name must be entirely inside the quotes"));
 			return FALSE;
 		}
@@ -165,10 +180,8 @@ static gchar *spawn_get_program_name(const gchar *command_line, GError **error)
 
 	if (open_quote)
 	{
-		g_set_error(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
-			/* TL note: from glib */
-			_("Text ended before matching quote was found for %c."
-			  " (The text was '%s')"), '"', command_line);
+		g_set_error_literal(error, G_SHELL_ERROR, G_SHELL_ERROR_BAD_QUOTING,
+			_("Text ended before matching quote was found"));
 		g_free(program);
 		return FALSE;
 	}
@@ -176,7 +189,7 @@ static gchar *spawn_get_program_name(const gchar *command_line, GError **error)
 	int argc;
 	char **argv;
 
-	if (!g_shell_parse_argv(command_line, &argc, &argv, error))
+	if (!spawn_parse_argv(command_line, &argc, &argv, error))
 		return FALSE;
 
 	/* empty string results in parse error, so argv[0] is not NULL */
@@ -237,8 +250,8 @@ gboolean spawn_check_command(const gchar *command_line, gboolean execute, GError
 
 		if (!executable)
 		{
-			g_set_error(error, G_SHELL_ERROR, G_SHELL_ERROR_FAILED,  /* or SPAWN error? */
-				_("Program '%s' not found"), program);
+			g_set_error_literal(error, G_SHELL_ERROR, G_SHELL_ERROR_FAILED,
+				_("Program not found"));
 			g_free(program);
 			return FALSE;
 		}
@@ -274,15 +287,14 @@ gboolean spawn_kill_process(GPid pid, GError **error)
 	{
 		gchar *message = g_win32_error_message(GetLastError());
 
-		g_set_error(error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED,
-			_("TerminateProcess() failed: %s"), message);
+		g_set_error_literal(error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, message);
 		g_free(message);
 		return FALSE;
 	}
 #else
 	if (kill(pid, SIGTERM))
 	{
-		g_set_error(error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, "%s", g_strerror(errno));
+		g_set_error_literal(error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, g_strerror(errno));
 		return FALSE;
 	}
 #endif
@@ -379,8 +391,12 @@ leave:
 		if (!message)
 			message = g_win32_error_message(GetLastError());
 
+	#ifdef SPAWN_TEST
 		failure = g_strdup_printf("%s() failed: %s", failed, message);
 		g_free(message);
+	#else
+		failure = message;
+	#endif
 	}
 
 	if (pipe_io)
@@ -546,7 +562,7 @@ static gboolean spawn_async_with_pipes(const gchar *working_directory, const gch
 
 	if (failure)
 	{
-		g_set_error(error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, "%s", failure);
+		g_set_error_literal(error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, failure);
 		g_free(failure);
 		return FALSE;
 	}
@@ -562,7 +578,7 @@ static gboolean spawn_async_with_pipes(const gchar *working_directory, const gch
 		int argc = 0;
 		char **cl_argv;
 
-		if (!g_shell_parse_argv(command_line, &cl_argc, &cl_argv, error))
+		if (!spawn_parse_argv(command_line, &cl_argc, &cl_argv, error))
 			return FALSE;
 
 		if (argv)