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         loaded = read_in_full(fd, buf, count);
  30         if (loaded == 0)
  31                 die("unexpected end of file");
  32         else if (loaded < 0)
  33                 die("read error (%s)", strerror(errno));
  34 }
  35
  36 void write_or_die(int fd, const void *buf, size_t count)
  37 {
  38         const char *p = buf;
  39         ssize_t written;
  40
  41         while (count > 0) {
  42                 written = xwrite(fd, p, count);
  43                 if (written == 0)
  44                         die("disk full?");
  45                 else if (written < 0) {
  46                         if (errno == EPIPE)
  47                                 exit(0);
  48                         die("write error (%s)", strerror(errno));
  49                 }
  50                 count -= written;
  51                 p += written;
  52         }
  53 }
  54
  55 int write_in_full(int fd, const void *buf, size_t count)
  56 {
  57         const char *p = buf;
  58         ssize_t total = 0;
  59         ssize_t wcount = 0;
  60
  61         while (count > 0) {
  62                 wcount = xwrite(fd, p, count);
  63                 if (wcount <= 0) {
  64                         if (total)
  65                                 return total;
  66                         else
  67                                 return wcount;
  68                 }
  69                 count -= wcount;
  70                 p += wcount;
  71                 total += wcount;
  72         }
  73
  74         return wcount;
  75 }
  76
  77 int write_or_whine_pipe(int fd, const void *buf, size_t count, const char *msg)
  78 {
  79         ssize_t written;
  80
  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         written = write_in_full(fd, buf, count);
 102         if (written == 0) {
 103                 fprintf(stderr, "%s: disk full?\n", msg);
 104                 return 0;
 105         }
 106         else if (written < 0) {
 107                 fprintf(stderr, "%s: write error (%s)\n",
 108                         msg, strerror(errno));
 109                 return 0;
 110         }
 111
 112         return 1;
 113 }