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