bash prompt: mention that PROMPT_COMMAND mode is faster

diff --git a/usage.c b/usage.c
index a2a667800474e315a362e1d0623c17dafaad1022..ed146453cabeb9e82bef0c5610cda47d1b2a0b1c 100644 (file)
--- a/usage.c
+++ b/usage.c
@@ -47,12 +47,19 @@ static void warn_builtin(const char *warn, va_list params)
        vreportf("warning: ", warn, params);
 }
 
+static int die_is_recursing_builtin(void)
+{
+       static int dying;
+       return dying++;
+}
+
 /* 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))
 {
@@ -64,6 +71,11 @@ void set_error_routine(void (*routine)(const char *err, va_list params))
        error_routine = routine;
 }
 
+void set_die_is_recursing_routine(int (*routine)(void))
+{
+       die_is_recursing = routine;
+}
+
 void NORETURN usagef(const char *err, ...)
 {
        va_list params;
@@ -82,6 +94,11 @@ 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);
@@ -94,6 +111,12 @@ void NORETURN die_errno(const char *fmt, ...)
        char str_error[256], *err;
        int i, j;
 
+       if (die_is_recursing()) {
+               fputs("fatal: recursion detected in die_errno handler\n",
+                       stderr);
+               exit(128);
+       }
+
        err = strerror(errno);
        for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {
                if ((str_error[j++] = err[i++]) != '%')
@@ -115,6 +138,7 @@ void NORETURN die_errno(const char *fmt, ...)
        va_end(params);
 }
 
+#undef error
 int error(const char *err, ...)
 {
        va_list params;