write_or_die.c

   1 #include "cache.h"
   2
   3 int read_in_full(int fd, void *buf, size_t count)
   4 {
   5         char *p = buf;
   6         ssize_t total = 0;
   7         ssize_t loaded = 0;
   8
   9         while (count > 0) {
  10                 loaded = xread(fd, p, count);
  11                 if (loaded <= 0) {
  12                         if (total)
  13                                 return total;
  14                         else
  15                                 return loaded;
  16                 }
  17                 count -= loaded;
  18                 p += loaded;
  19                 total += loaded;
  20         }
  21
  22         return total;
  23 }
  24
  25 void read_or_die(int fd, void *buf, size_t count)
  26 {
  27         ssize_t loaded;
  28
  29         if (!count)
  30                 return;
  31         loaded = read_in_full(fd, buf, count);
  32         if (loaded == 0)
  33                 die("unexpected end of file");
  34         else if (loaded < 0)
  35                 die("read error (%s)", strerror(errno));
  36 }
  37
  38 int write_in_full(int fd, const void *buf, size_t count)
  39 {
  40         const char *p = buf;
  41         ssize_t total = 0;
  42
  43         while (count > 0) {
  44                 size_t written = xwrite(fd, p, count);
  45                 if (written < 0)
  46                         return -1;
  47                 if (!written) {
  48                         errno = ENOSPC;
  49                         return -1;
  50                 }
  51                 count -= written;
  52                 p += written;
  53                 total += written;
  54         }
  55
  56         return total;
  57 }
  58
  59 void write_or_die(int fd, const void *buf, size_t count)
  60 {
  61         ssize_t written;
  62
  63         if (!count)
  64                 return;
  65         written = write_in_full(fd, buf, count);
  66         if (written == 0)
  67                 die("disk full?");
  68         else if (written < 0) {
  69                 if (errno == EPIPE)
  70                         exit(0);
  71                 die("write error (%s)", strerror(errno));
  72         }
  73 }
  74
  75 int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg)
  76 {
  77         ssize_t written;
  78
  79         if (!count)
  80                 return 1;
  81         written = write_in_full(fd, buf, count);
  82         if (written == 0) {
  83                 fprintf(stderr, "%s: disk full?\n", msg);
  84                 return 0;
  85         }
  86         else if (written < 0) {
  87                 if (errno == EPIPE)
  88                         exit(0);
  89                 fprintf(stderr, "%s: write error (%s)\n",
  90                         msg, strerror(errno));
  91                 return 0;
  92         }
  93
  94         return 1;
  95 }
  96
  97 int write_or_whine(int fd, const void *buf, size_t count, const char *msg)
  98 {
  99         ssize_t written;
 100
 101         if (!count)
 102                 return 1;
 103         written = write_in_full(fd, buf, count);
 104         if (written == 0) {
 105                 fprintf(stderr, "%s: disk full?\n", msg);
 106                 return 0;
 107         }
 108         else if (written < 0) {
 109                 fprintf(stderr, "%s: write error (%s)\n",
 110                         msg, strerror(errno));
 111                 return 0;
 112         }
 113
 114         return 1;
 115 }