usage: allow pluggable die-recursion checks
When any git code calls die or die_errno, we use a counter to detect recursion into the die functions from any of the helper functions. However, such a simple counter is not good enough for threaded programs, which may call die from a sub-thread, killing only the sub-thread (but incrementing the counter for everyone). Rather than try to deal with threads ourselves here, let's just allow callers to plug in their own recursion-detection function. This is similar to how we handle the die routine (the caller plugs in a die routine which may kill only the sub-thread). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King committed
Apr 16, 2013 at 15:46 UTC
c19a490e37181de8fa94ae1074af4b9f9a518f95
2 files changed
+15
-6
git-compat-util.h
+1
@@ -301,6 +301,7 @@ extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)))
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extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
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extern void set_error_routine(void (*routine)(const char *err, va_list params));
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+extern void set_die_is_recursing_routine(int (*routine)(void));
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extern int prefixcmp(const char *str, const char *prefix);
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extern int suffixcmp(const char *str, const char *suffix);
usage.c
+14
-6
@@ -6,8 +6,6 @@
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#include "git-compat-util.h"
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#include "cache.h"
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-static int dying;
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-
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void vreportf(const char *prefix, const char *err, va_list params)
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{
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char msg[4096];
@@ -49,12 +47,19 @@ static void warn_builtin(const char *warn, va_list params)
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vreportf("warning: ", warn, params);
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}
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+static int die_is_recursing_builtin(void)
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+{
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+ static int dying;
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+ return dying++;
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+}
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+
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/* If we are in a dlopen()ed .so write to a global variable would segfault
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* (ugh), so keep things static. */
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static NORETURN_PTR void (*usage_routine)(const char *err, va_list params) = usage_builtin;
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static NORETURN_PTR void (*die_routine)(const char *err, va_list params) = die_builtin;
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static void (*error_routine)(const char *err, va_list params) = error_builtin;
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static void (*warn_routine)(const char *err, va_list params) = warn_builtin;
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+static int (*die_is_recursing)(void) = die_is_recursing_builtin;
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void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params))
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{
@@ -66,6 +71,11 @@ void set_error_routine(void (*routine)(const char *err, va_list params))
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error_routine = routine;
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}
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+void set_die_is_recursing_routine(int (*routine)(void))
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+{
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+ die_is_recursing = routine;
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+}
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+
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void NORETURN usagef(const char *err, ...)
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{
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va_list params;
@@ -84,11 +94,10 @@ void NORETURN die(const char *err, ...)
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{
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va_list params;
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- if (dying) {
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+ if (die_is_recursing()) {
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fputs("fatal: recursion detected in die handler\n", stderr);
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exit(128);
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}
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- dying = 1;
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va_start(params, err);
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die_routine(err, params);
@@ -102,12 +111,11 @@ void NORETURN die_errno(const char *fmt, ...)
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char str_error[256], *err;
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int i, j;
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- if (dying) {
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+ if (die_is_recursing()) {
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fputs("fatal: recursion detected in die_errno handler\n",
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stderr);
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exit(128);
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}
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- dying = 1;
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err = strerror(errno);
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for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {