usage.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  */
   6 #include "git-compat-util.h"
   7
   8 void vreport(const char *prefix, const char *err, va_list params)
   9 {
  10         char msg[1024];
  11         vsnprintf(msg, sizeof(msg), err, params);
  12         fprintf(stderr, "%s%s\n", prefix, msg);
  13 }
  14
  15 static NORETURN void usage_builtin(const char *err)
  16 {
  17         fprintf(stderr, "usage: %s\n", err);
  18         exit(129);
  19 }
  20
  21 static NORETURN void die_builtin(const char *err, va_list params)
  22 {
  23         vreport("fatal: ", err, params);
  24         exit(128);
  25 }
  26
  27 static void error_builtin(const char *err, va_list params)
  28 {
  29         vreport("error: ", err, params);
  30 }
  31
  32 static void warn_builtin(const char *warn, va_list params)
  33 {
  34         vreport("warning: ", warn, params);
  35 }
  36
  37 typedef void (*die_fn_t)(const char *err, va_list params) NORETURN;
  38
  39 static DWORD tls_index;
  40
  41 static void tls_init(void) __attribute__((constructor));
  42 static void tls_init(void)
  43 {
  44         tls_index = TlsAlloc();
  45 }
  46
  47 struct routines {
  48         die_fn_t die_routine;
  49 };
  50 /* If we are in a dlopen()ed .so write to a global variable would segfault
  51  * (ugh), so keep things static. */
  52 static void (*usage_routine)(const char *err) NORETURN = usage_builtin;
  53 static void (*error_routine)(const char *err, va_list params) = error_builtin;
  54 static void (*warn_routine)(const char *err, va_list params) = warn_builtin;
  55
  56 void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN)
  57 {
  58         struct routines *r = TlsGetValue(tls_index);
  59         if (r == NULL) {
  60                 /* avoid die()! */
  61                 r = calloc(sizeof(*r), 1);
  62                 if (r == NULL) {
  63                         fprintf(stderr, "cannot allocate thread-local storage");
  64                         return;
  65                 }
  66                 TlsSetValue(tls_index, r);
  67         }
  68         r->die_routine = routine;
  69 }
  70
  71 void usage(const char *err)
  72 {
  73         usage_routine(err);
  74 }
  75
  76 void die(const char *err, ...)
  77 {
  78         va_list params;
  79         struct routines *r = TlsGetValue(tls_index);
  80
  81         va_start(params, err);
  82         if (r == NULL || r->die_routine == NULL)
  83                 die_builtin(err, params);
  84         else
  85                 r->die_routine(err, params);
  86         va_end(params);
  87 }
  88
  89 int error(const char *err, ...)
  90 {
  91         va_list params;
  92
  93         va_start(params, err);
  94         error_routine(err, params);
  95         va_end(params);
  96         return -1;
  97 }
  98
  99 void warning(const char *warn, ...)
 100 {
 101         va_list params;
 102
 103         va_start(params, warn);
 104         warn_routine(warn, params);
 105         va_end(params);
 106 }