Add an example/zcat -fail-if-unsandboxed flag
diff --git a/example/zcat/zcat.c b/example/zcat/zcat.c
index 4d7398b..87af5e3 100644
--- a/example/zcat/zcat.c
+++ b/example/zcat/zcat.c
@@ -80,12 +80,70 @@
uint8_t work_buffer[1];
#endif
+// ----
+
+static bool sandboxed = false;
+
+struct {
+ int remaining_argc;
+ char** remaining_argv;
+
+ bool fail_if_unsandboxed;
+} flags = {0};
+
+const char* //
+parse_flags(int argc, char** argv) {
+ int c = (argc > 0) ? 1 : 0; // Skip argv[0], the program name.
+ for (; c < argc; c++) {
+ char* arg = argv[c];
+ if (*arg++ != '-') {
+ break;
+ }
+
+ // A double-dash "--foo" is equivalent to a single-dash "-foo". As special
+ // cases, a bare "-" is not a flag (some programs may interpret it as
+ // stdin) and a bare "--" means to stop parsing flags.
+ if (*arg == '\x00') {
+ break;
+ } else if (*arg == '-') {
+ arg++;
+ if (*arg == '\x00') {
+ c++;
+ break;
+ }
+ }
+
+ if (!strcmp(arg, "fail-if-unsandboxed")) {
+ flags.fail_if_unsandboxed = true;
+ continue;
+ }
+
+ return "main: unrecognized flag argument";
+ }
+
+ flags.remaining_argc = argc - c;
+ flags.remaining_argv = argv + c;
+ return NULL;
+}
+
+// ----
+
// ignore_return_value suppresses errors from -Wall -Werror.
static void //
ignore_return_value(int ignored) {}
-static const char* //
-decode() {
+#include <stdio.h>
+
+const char* //
+main1(int argc, char** argv) {
+ const char* z = parse_flags(argc, argv);
+ if (z) {
+ return z;
+ }
+ if (flags.fail_if_unsandboxed && !sandboxed) {
+ return "main: unsandboxed";
+ }
+
wuffs_gzip__decoder dec;
wuffs_base__status status =
wuffs_gzip__decoder__initialize(&dec, sizeof dec, WUFFS_VERSION, 0);
@@ -148,7 +206,7 @@
wuffs_base__io_buffer__compact(&src);
if (src.meta.wi == src.data.len) {
- return "internal error: no I/O progress possible";
+ return "main: internal error: no I/O progress possible";
}
}
}
@@ -184,9 +242,10 @@
main(int argc, char** argv) {
#if defined(WUFFS_EXAMPLE_USE_SECCOMP)
prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT);
+ sandboxed = true;
#endif
- int exit_code = compute_exit_code(decode());
+ int exit_code = compute_exit_code(main1(argc, argv));
#if defined(WUFFS_EXAMPLE_USE_SECCOMP)
// Call SYS_exit explicitly instead of SYS_exit_group implicitly.
