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 #include "cache.h"
   8
   9 static FILE *error_handle;
  10 static int tweaked_error_buffering;
  11
  12 void vreportf(const char *prefix, const char *err, va_list params)
  13 {
  14         FILE *fh = error_handle ? error_handle : stderr;
  15
  16         fflush(fh);
  17         if (!tweaked_error_buffering) {
  18                 setvbuf(fh, NULL, _IOLBF, 0);
  19                 tweaked_error_buffering = 1;
  20         }
  21
  22         fputs(prefix, fh);
  23         vfprintf(fh, err, params);
  24         fputc('\n', fh);
  25 }
  26
  27 static NORETURN void usage_builtin(const char *err, va_list params)
  28 {
  29         vreportf("usage: ", err, params);
  30         exit(129);
  31 }
  32
  33 static NORETURN void die_builtin(const char *err, va_list params)
  34 {
  35         vreportf("fatal: ", err, params);
  36         exit(128);
  37 }
  38
  39 static void error_builtin(const char *err, va_list params)
  40 {
  41         vreportf("error: ", err, params);
  42 }
  43
  44 static void warn_builtin(const char *warn, va_list params)
  45 {
  46         vreportf("warning: ", warn, params);
  47 }
  48
  49 static int die_is_recursing_builtin(void)
  50 {
  51         static int dying;
  52         return dying++;
  53 }
  54
  55 /* If we are in a dlopen()ed .so write to a global variable would segfault
  56  * (ugh), so keep things static. */
  57 static NORETURN_PTR void (*usage_routine)(const char *err, va_list params) = usage_builtin;
  58 static NORETURN_PTR void (*die_routine)(const char *err, va_list params) = die_builtin;
  59 static void (*error_routine)(const char *err, va_list params) = error_builtin;
  60 static void (*warn_routine)(const char *err, va_list params) = warn_builtin;
  61 static int (*die_is_recursing)(void) = die_is_recursing_builtin;
  62
  63 void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params))
  64 {
  65         die_routine = routine;
  66 }
  67
  68 void set_error_routine(void (*routine)(const char *err, va_list params))
  69 {
  70         error_routine = routine;
  71 }
  72
  73 void set_die_is_recursing_routine(int (*routine)(void))
  74 {
  75         die_is_recursing = routine;
  76 }
  77
  78 void set_error_handle(FILE *fh)
  79 {
  80         error_handle = fh;
  81         tweaked_error_buffering = 0;
  82 }
  83
  84 void NORETURN usagef(const char *err, ...)
  85 {
  86         va_list params;
  87
  88         va_start(params, err);
  89         usage_routine(err, params);
  90         va_end(params);
  91 }
  92
  93 void NORETURN usage(const char *err)
  94 {
  95         usagef("%s", err);
  96 }
  97
  98 void NORETURN die(const char *err, ...)
  99 {
 100         va_list params;
 101
 102         if (die_is_recursing()) {
 103                 fputs("fatal: recursion detected in die handler\n", stderr);
 104                 exit(128);
 105         }
 106
 107         va_start(params, err);
 108         die_routine(err, params);
 109         va_end(params);
 110 }
 111
 112 static const char *fmt_with_err(char *buf, int n, const char *fmt)
 113 {
 114         char str_error[256], *err;
 115         int i, j;
 116
 117         err = strerror(errno);
 118         for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {
 119                 if ((str_error[j++] = err[i++]) != '%')
 120                         continue;
 121                 if (j < sizeof(str_error) - 1) {
 122                         str_error[j++] = '%';
 123                 } else {
 124                         /* No room to double the '%', so we overwrite it with
 125                          * '\0' below */
 126                         j--;
 127                         break;
 128                 }
 129         }
 130         str_error[j] = 0;
 131         snprintf(buf, n, "%s: %s", fmt, str_error);
 132         return buf;
 133 }
 134
 135 void NORETURN die_errno(const char *fmt, ...)
 136 {
 137         char buf[1024];
 138         va_list params;
 139
 140         if (die_is_recursing()) {
 141                 fputs("fatal: recursion detected in die_errno handler\n",
 142                         stderr);
 143                 exit(128);
 144         }
 145
 146         va_start(params, fmt);
 147         die_routine(fmt_with_err(buf, sizeof(buf), fmt), params);
 148         va_end(params);
 149 }
 150
 151 #undef error
 152 int error(const char *err, ...)
 153 {
 154         va_list params;
 155
 156         va_start(params, err);
 157         error_routine(err, params);
 158         va_end(params);
 159         return -1;
 160 }
 161
 162 void warning(const char *warn, ...)
 163 {
 164         va_list params;
 165
 166         va_start(params, warn);
 167         warn_routine(warn, params);
 168         va_end(params);
 169 }