copy.c

   1 #include "cache.h"
   2
   3 int copy_fd(int ifd, int ofd)
   4 {
   5         while (1) {
   6                 char buffer[8192];
   7                 char *buf = buffer;
   8                 ssize_t len = xread(ifd, buffer, sizeof(buffer));
   9                 if (!len)
  10                         break;
  11                 if (len < 0) {
  12                         int save_errno = errno;
  13                         close(ifd);
  14                         error("copy-fd: read returned %s",
  15                               strerror(save_errno));
  16                         errno = save_errno;
  17                         return -1;
  18                 }
  19                 while (len) {
  20                         int written = xwrite(ofd, buf, len);
  21                         if (written > 0) {
  22                                 buf += written;
  23                                 len -= written;
  24                         }
  25                         else if (!written) {
  26                                 close(ifd);
  27                                 error("copy-fd: write returned 0");
  28                                 errno = EAGAIN;
  29                                 return -1;
  30                         } else {
  31                                 int save_errno = errno;
  32                                 close(ifd);
  33                                 error("copy-fd: write returned %s",
  34                                       strerror(save_errno));
  35                                 errno = save_errno;
  36                                 return -1;
  37                         }
  38                 }
  39         }
  40         close(ifd);
  41         return 0;
  42 }
  43
  44 static int copy_times(const char *dst, const char *src)
  45 {
  46         struct stat st;
  47         struct utimbuf times;
  48         if (stat(src, &st) < 0)
  49                 return -1;
  50         times.actime = st.st_atime;
  51         times.modtime = st.st_mtime;
  52         if (utime(dst, &times) < 0)
  53                 return -1;
  54         return 0;
  55 }
  56
  57 int copy_file(const char *dst, const char *src, int mode)
  58 {
  59         int fdi, fdo, status;
  60
  61         mode = (mode & 0111) ? 0777 : 0666;
  62         if ((fdi = open(src, O_RDONLY)) < 0)
  63                 return fdi;
  64         if ((fdo = open(dst, O_WRONLY | O_CREAT | O_EXCL, mode)) < 0) {
  65                 close(fdi);
  66                 return fdo;
  67         }
  68         status = copy_fd(fdi, fdo);
  69         if (close(fdo) != 0)
  70                 return error("%s: close error: %s", dst, strerror(errno));
  71
  72         if (!status && adjust_shared_perm(dst))
  73                 return -1;
  74
  75         return status;
  76 }
  77
  78 int copy_file_with_time(const char *dst, const char *src, int mode)
  79 {
  80         int status = copy_file(dst, src, mode);
  81         if (!status)
  82                 return copy_times(dst, src);
  83         return status;
  84 }