1 files changed, 307 insertions, 0 deletions
diff --git a/third_party/git/usage.c b/third_party/git/usage.c
new file mode 100644
index 000000000000..58fb5fff5f24
--- /dev/null
+++ b/third_party/git/usage.c
@@ -0,0 +1,307 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "git-compat-util.h"
+#include "cache.h"
+
+void vreportf(const char *prefix, const char *err, va_list params)
+{
+	char msg[4096];
+	char *p, *pend = msg + sizeof(msg);
+	size_t prefix_len = strlen(prefix);
+
+	if (sizeof(msg) <= prefix_len) {
+		fprintf(stderr, "BUG!!! too long a prefix '%s'\n", prefix);
+		abort();
+	}
+	memcpy(msg, prefix, prefix_len);
+	p = msg + prefix_len;
+	if (vsnprintf(p, pend - p, err, params) < 0)
+		*p = '\0'; /* vsnprintf() failed, clip at prefix */
+
+	for (; p != pend - 1 && *p; p++) {
+		if (iscntrl(*p) && *p != '\t' && *p != '\n')
+			*p = '?';
+	}
+
+	*(p++) = '\n'; /* we no longer need a NUL */
+	fflush(stderr);
+	write_in_full(2, msg, p - msg);
+}
+
+static NORETURN void usage_builtin(const char *err, va_list params)
+{
+	vreportf("usage: ", err, params);
+
+	/*
+	 * When we detect a usage error *before* the command dispatch in
+	 * cmd_main(), we don't know what verb to report.  Force it to this
+	 * to facilitate post-processing.
+	 */
+	trace2_cmd_name("_usage_");
+
+	/*
+	 * Currently, the (err, params) are usually just the static usage
+	 * string which isn't very useful here.  Usually, the call site
+	 * manually calls fprintf(stderr,...) with the actual detailed
+	 * syntax error before calling usage().
+	 *
+	 * TODO It would be nice to update the call sites to pass both
+	 * the static usage string and the detailed error message.
+	 */
+
+	exit(129);
+}
+
+static NORETURN void die_builtin(const char *err, va_list params)
+{
+	/*
+	 * We call this trace2 function first and expect it to va_copy 'params'
+	 * before using it (because an 'ap' can only be walked once).
+	 */
+	trace2_cmd_error_va(err, params);
+
+	vreportf("fatal: ", err, params);
+
+	exit(128);
+}
+
+static void error_builtin(const char *err, va_list params)
+{
+	/*
+	 * We call this trace2 function first and expect it to va_copy 'params'
+	 * before using it (because an 'ap' can only be walked once).
+	 */
+	trace2_cmd_error_va(err, params);
+
+	vreportf("error: ", err, params);
+}
+
+static void warn_builtin(const char *warn, va_list params)
+{
+	vreportf("warning: ", warn, params);
+}
+
+static int die_is_recursing_builtin(void)
+{
+	static int dying;
+	/*
+	 * Just an arbitrary number X where "a < x < b" where "a" is
+	 * "maximum number of pthreads we'll ever plausibly spawn" and
+	 * "b" is "something less than Inf", since the point is to
+	 * prevent infinite recursion.
+	 */
+	static const int recursion_limit = 1024;
+
+	dying++;
+	if (dying > recursion_limit) {
+		return 1;
+	} else if (dying == 2) {
+		warning("die() called many times. Recursion error or racy threaded death!");
+		return 0;
+	} else {
+		return 0;
+	}
+}
+
+/* If we are in a dlopen()ed .so write to a global variable would segfault
+ * (ugh), so keep things static. */
+static NORETURN_PTR void (*usage_routine)(const char *err, va_list params) = usage_builtin;
+static NORETURN_PTR void (*die_routine)(const char *err, va_list params) = die_builtin;
+static void (*error_routine)(const char *err, va_list params) = error_builtin;
+static void (*warn_routine)(const char *err, va_list params) = warn_builtin;
+static int (*die_is_recursing)(void) = die_is_recursing_builtin;
+
+void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params))
+{
+	die_routine = routine;
+}
+
+void set_error_routine(void (*routine)(const char *err, va_list params))
+{
+	error_routine = routine;
+}
+
+void (*get_error_routine(void))(const char *err, va_list params)
+{
+	return error_routine;
+}
+
+void set_warn_routine(void (*routine)(const char *warn, va_list params))
+{
+	warn_routine = routine;
+}
+
+void (*get_warn_routine(void))(const char *warn, va_list params)
+{
+	return warn_routine;
+}
+
+void set_die_is_recursing_routine(int (*routine)(void))
+{
+	die_is_recursing = routine;
+}
+
+void NORETURN usagef(const char *err, ...)
+{
+	va_list params;
+
+	va_start(params, err);
+	usage_routine(err, params);
+	va_end(params);
+}
+
+void NORETURN usage(const char *err)
+{
+	usagef("%s", err);
+}
+
+void NORETURN die(const char *err, ...)
+{
+	va_list params;
+
+	if (die_is_recursing()) {
+		fputs("fatal: recursion detected in die handler\n", stderr);
+		exit(128);
+	}
+
+	va_start(params, err);
+	die_routine(err, params);
+	va_end(params);
+}
+
+static const char *fmt_with_err(char *buf, int n, const char *fmt)
+{
+	char str_error[256], *err;
+	int i, j;
+
+	err = strerror(errno);
+	for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {
+		if ((str_error[j++] = err[i++]) != '%')
+			continue;
+		if (j < sizeof(str_error) - 1) {
+			str_error[j++] = '%';
+		} else {
+			/* No room to double the '%', so we overwrite it with
+			 * '\0' below */
+			j--;
+			break;
+		}
+	}
+	str_error[j] = 0;
+	/* Truncation is acceptable here */
+	snprintf(buf, n, "%s: %s", fmt, str_error);
+	return buf;
+}
+
+void NORETURN die_errno(const char *fmt, ...)
+{
+	char buf[1024];
+	va_list params;
+
+	if (die_is_recursing()) {
+		fputs("fatal: recursion detected in die_errno handler\n",
+			stderr);
+		exit(128);
+	}
+
+	va_start(params, fmt);
+	die_routine(fmt_with_err(buf, sizeof(buf), fmt), params);
+	va_end(params);
+}
+
+#undef error_errno
+int error_errno(const char *fmt, ...)
+{
+	char buf[1024];
+	va_list params;
+
+	va_start(params, fmt);
+	error_routine(fmt_with_err(buf, sizeof(buf), fmt), params);
+	va_end(params);
+	return -1;
+}
+
+#undef error
+int error(const char *err, ...)
+{
+	va_list params;
+
+	va_start(params, err);
+	error_routine(err, params);
+	va_end(params);
+	return -1;
+}
+
+void warning_errno(const char *warn, ...)
+{
+	char buf[1024];
+	va_list params;
+
+	va_start(params, warn);
+	warn_routine(fmt_with_err(buf, sizeof(buf), warn), params);
+	va_end(params);
+}
+
+void warning(const char *warn, ...)
+{
+	va_list params;
+
+	va_start(params, warn);
+	warn_routine(warn, params);
+	va_end(params);
+}
+
+/* Only set this, ever, from t/helper/, when verifying that bugs are caught. */
+int BUG_exit_code;
+
+static NORETURN void BUG_vfl(const char *file, int line, const char *fmt, va_list params)
+{
+	char prefix[256];
+
+	/* truncation via snprintf is OK here */
+	if (file)
+		snprintf(prefix, sizeof(prefix), "BUG: %s:%d: ", file, line);
+	else
+		snprintf(prefix, sizeof(prefix), "BUG: ");
+
+	vreportf(prefix, fmt, params);
+	if (BUG_exit_code)
+		exit(BUG_exit_code);
+	abort();
+}
+
+#ifdef HAVE_VARIADIC_MACROS
+NORETURN void BUG_fl(const char *file, int line, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	BUG_vfl(file, line, fmt, ap);
+	va_end(ap);
+}
+#else
+NORETURN void BUG(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	BUG_vfl(NULL, 0, fmt, ap);
+	va_end(ap);
+}
+#endif
+
+#ifdef SUPPRESS_ANNOTATED_LEAKS
+void unleak_memory(const void *ptr, size_t len)
+{
+	static struct suppressed_leak_root {
+		struct suppressed_leak_root *next;
+		char data[FLEX_ARRAY];
+	} *suppressed_leaks;
+	struct suppressed_leak_root *root;
+
+	FLEX_ALLOC_MEM(root, data, ptr, len);
+	root->next = suppressed_leaks;
+	suppressed_leaks = root;
+}
+#endif