From d4f4a4d040ef47a5e82dffd0f067e92716606ddf Mon Sep 17 00:00:00 2001 From: Jia Tan Date: Tue, 14 Nov 2023 20:27:04 +0800 Subject: [PATCH] xz: Detect when all data will be written to standard out earlier. If the -c, --stdout argument is not used, then we can still detect when the data will be written to standard out if all of the provided filenames are "-" (denoting standard in) or if no filenames are provided. --- src/xz/args.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/src/xz/args.c b/src/xz/args.c index 8b481c93..e3cddda3 100644 --- a/src/xz/args.c +++ b/src/xz/args.c @@ -842,6 +842,27 @@ args_parse(args_info *args, int argc, char **argv) args->arg_count = (unsigned int)(argc - optind); } + // If all of the filenames provided are "-" (more than one "-" + // could be specified) or no filenames are provided, then we are + // only going to be writing to standard out. However if --files or + // --files0 is used, then we will not be writing to standard out. + if (!opt_stdout && args->files_name == NULL) { + uint32_t i; + + for (i = 0; i < args->arg_count; i++) { + const char *name = args->arg_names[i]; + + // getopt_long() will not give us an empty string + // as an argument name here so we don't need to + // check if name[0] is a NULL terminator. + if (name[0] != '-' && name[1] != '\0') + break; + } + + // Set opt_stdout if the loop did not exit early. + opt_stdout = i == args->arg_count; + } + return; }