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 void vreportf(const char *prefix, const char *err, va_list params)
  10 {
  11         char msg[4096];
  12         vsnprintf(msg, sizeof(msg), err, params);
  13         fprintf(stderr, "%s%s\n", prefix, msg);
  14 }
  15
  16 void vwritef(int fd, const char *prefix, const char *err, va_list params)
  17 {
  18         char msg[4096];
  19         int len = vsnprintf(msg, sizeof(msg), err, params);
  20         if (len > sizeof(msg))
  21                 len = sizeof(msg);
  22
  23         write_in_full(fd, prefix, strlen(prefix));
  24         write_in_full(fd, msg, len);
  25         write_in_full(fd, "\n", 1);
  26 }
  27
  28 static NORETURN void usage_builtin(const char *err, va_list params)
  29 {
  30         vreportf("usage: ", err, params);
  31         exit(129);
  32 }
  33
  34 static NORETURN void die_builtin(const char *err, va_list params)
  35 {
  36         vreportf("fatal: ", err, params);
  37         exit(128);
  38 }
  39
  40 static void error_builtin(const char *err, va_list params)
  41 {
  42         vreportf("error: ", err, params);
  43 }
  44
  45 static void warn_builtin(const char *warn, va_list params)
  46 {
  47         vreportf("warning: ", warn, params);
  48 }
  49
  50 static int die_is_recursing_builtin(void)
  51 {
  52         static int dying;
  53         return dying++;
  54 }
  55
  56 /* If we are in a dlopen()ed .so write to a global variable would segfault
  57  * (ugh), so keep things static. */
  58 static NORETURN_PTR void (*usage_routine)(const char *err, va_list params) = usage_builtin;
  59 static NORETURN_PTR void (*die_routine)(const char *err, va_list params) = die_builtin;
  60 static void (*error_routine)(const char *err, va_list params) = error_builtin;
  61 static void (*warn_routine)(const char *err, va_list params) = warn_builtin;
  62 static int (*die_is_recursing)(void) = die_is_recursing_builtin;
  63
  64 void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params))
  65 {
  66         die_routine = routine;
  67 }
  68
  69 void set_error_routine(void (*routine)(const char *err, va_list params))
  70 {
  71         error_routine = routine;
  72 }
  73
  74 void set_die_is_recursing_routine(int (*routine)(void))
  75 {
  76         die_is_recursing = routine;
  77 }
  78
  79 void NORETURN usagef(const char *err, ...)
  80 {
  81         va_list params;
  82
  83         va_start(params, err);
  84         usage_routine(err, params);
  85         va_end(params);
  86 }
  87
  88 void NORETURN usage(const char *err)
  89 {
  90         usagef("%s", err);
  91 }
  92
  93 void NORETURN die(const char *err, ...)
  94 {
  95         va_list params;
  96
  97         if (die_is_recursing()) {
  98                 fputs("fatal: recursion detected in die handler\n", stderr);
  99                 exit(128);
 100         }
 101
 102         va_start(params, err);
 103         die_routine(err, params);
 104         va_end(params);
 105 }
 106
 107 void NORETURN die_errno(const char *fmt, ...)
 108 {
 109         va_list params;
 110         char fmt_with_err[1024];
 111         char str_error[256], *err;
 112         int i, j;
 113
 114         if (die_is_recursing()) {
 115                 fputs("fatal: recursion detected in die_errno handler\n",
 116                         stderr);
 117                 exit(128);
 118         }
 119
 120         err = strerror(errno);
 121         for (i = j = 0; err[i] && j < sizeof(str_error) - 1; ) {
 122                 if ((str_error[j++] = err[i++]) != '%')
 123                         continue;
 124                 if (j < sizeof(str_error) - 1) {
 125                         str_error[j++] = '%';
 126                 } else {
 127                         /* No room to double the '%', so we overwrite it with
 128                          * '\0' below */
 129                         j--;
 130                         break;
 131                 }
 132         }
 133         str_error[j] = 0;
 134         snprintf(fmt_with_err, sizeof(fmt_with_err), "%s: %s", fmt, str_error);
 135
 136         va_start(params, fmt);
 137         die_routine(fmt_with_err, params);
 138         va_end(params);
 139 }
 140
 141 #undef error
 142 int error(const char *err, ...)
 143 {
 144         va_list params;
 145
 146         va_start(params, err);
 147         error_routine(err, params);
 148         va_end(params);
 149         return -1;
 150 }
 151
 152 void warning(const char *warn, ...)
 153 {
 154         va_list params;
 155
 156         va_start(params, warn);
 157         warn_routine(warn, params);
 158         va_end(params);
 159 }