release/src/router/dnscrypt/src/proxy/safe_rw.c

   1
   2 #include <config.h>
   3 #include <sys/types.h>
   4
   5 #include <assert.h>
   6 #include <errno.h>
   7 #ifndef _WIN32
   8 # include <poll.h>
   9 #endif
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12
  13 #include "safe_rw.h"
  14
  15 #ifndef _WIN32
  16 ssize_t
  17 safe_write(const int fd, const void * const buf_, size_t count,
  18            const int timeout)
  19 {
  20     struct pollfd  pfd;
  21     const char    *buf = (const char *) buf_;
  22     ssize_t        written;
  23
  24     pfd.fd = fd;
  25     pfd.events = POLLOUT;
  26
  27     while (count > (size_t) 0) {
  28         while ((written = write(fd, buf, count)) <= (ssize_t) 0) {
  29             if (errno == EAGAIN) {
  30                 if (poll(&pfd, (nfds_t) 1, timeout) == 0) {
  31                     errno = ETIMEDOUT;
  32                     goto ret;
  33                 }
  34             } else if (errno != EINTR) {
  35                 goto ret;
  36             }
  37         }
  38         buf += written;
  39         count -= (size_t) written;
  40     }
  41 ret:
  42     return (ssize_t) (buf - (const char *) buf_);
  43 }
  44
  45 ssize_t
  46 safe_read(const int fd, void * const buf_, size_t count)
  47 {
  48     unsigned char *buf = (unsigned char *) buf_;
  49     ssize_t        readnb;
  50
  51     do {
  52         while ((readnb = read(fd, buf, count)) < (ssize_t) 0 &&
  53                errno == EINTR);
  54         if (readnb < (ssize_t) 0) {
  55             return readnb;
  56         }
  57         if (readnb == (ssize_t) 0) {
  58             break;
  59         }
  60         count -= (size_t) readnb;
  61         buf += readnb;
  62     } while (count > (ssize_t) 0);
  63
  64     return (ssize_t) (buf - (unsigned char *) buf_);
  65 }
  66
  67 ssize_t
  68 safe_read_partial(const int fd, void * const buf_, const size_t max_count)
  69 {
  70     unsigned char * const buf = (unsigned char *) buf_;
  71     ssize_t               readnb;
  72
  73     while ((readnb = read(fd, buf, max_count)) < (ssize_t) 0 &&
  74            errno == EINTR);
  75
  76     return readnb;
  77 }
  78
  79 #else /* _WIN32 */
  80
  81 ssize_t
  82 safe_write(const int fd, const void * const buf_, size_t count,
  83            const int timeout)
  84 {
  85     assert(fd != -1);
  86     assert(buf_ != NULL);
  87     assert(count > (size_t) 0U);
  88     (void) timeout;
  89
  90     return -1;
  91 }
  92
  93 ssize_t
  94 safe_read(const int fd, void * const buf_, size_t count)
  95 {
  96     assert(fd != -1);
  97     assert(buf_ != NULL);
  98     assert(count > (size_t) 0U);
  99
 100     return -1;
 101 }
 102
 103 ssize_t
 104 safe_read_partial(const int fd, void * const buf_, const size_t max_count)
 105 {
 106     assert(fd != -1);
 107     assert(buf_ != NULL);
 108     assert(max_count > (size_t) 0U);
 109
 110     return -1;
 111 }
 112
 113 #endif