dispatch-1.0/testing/dispatch_read.c

   1 /*
   2  * Copyright (c) 2008-2009 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_APACHE_LICENSE_HEADER_START@
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  *
  18  * @APPLE_APACHE_LICENSE_HEADER_END@
  19  */
  20
  21 #include "config/config.h"
  22
  23 #include <sys/stat.h>
  24 #include <assert.h>
  25 #include <fcntl.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <unistd.h>
  29 #include <errno.h>
  30
  31 #include <dispatch/dispatch.h>
  32
  33 #include "dispatch_test.h"
  34
  35 static size_t bytes_total;
  36 static size_t bytes_read;
  37
  38 int main(void)
  39 {
  40         const char *path = "/usr/share/dict/words";
  41         struct stat sb;
  42
  43         test_start("Dispatch Source Read");
  44
  45         int infd = open(path, O_RDONLY);
  46         if (infd == -1) {
  47                 perror(path);
  48                 exit(EXIT_FAILURE);
  49         }
  50         if (fstat(infd, &sb) == -1) {
  51                 perror(path);
  52                 exit(EXIT_FAILURE);
  53         }
  54         bytes_total = sb.st_size;
  55
  56         if (fcntl(infd, F_SETFL, O_NONBLOCK) != 0) {
  57                 perror(path);
  58                 exit(EXIT_FAILURE);
  59         }
  60
  61         dispatch_queue_t main_q = dispatch_get_main_queue();
  62         test_ptr_notnull("dispatch_get_main_queue", main_q);
  63
  64         dispatch_source_t reader;
  65
  66         reader = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, infd, 0, main_q);
  67         test_ptr_notnull("DISPATCH_SOURCE_TYPE_READ", reader);
  68
  69         dispatch_source_set_event_handler(reader, ^{
  70                         size_t estimated = dispatch_source_get_data(reader);
  71                         printf("bytes available: %zu\n", estimated);
  72                         const ssize_t bufsiz = 1024*500; // 500 KB buffer
  73                         static char buffer[1024*500];   // 500 KB buffer
  74                         ssize_t actual = read(infd, buffer, sizeof(buffer));
  75                         bytes_read += actual;
  76                         printf("bytes read: %zd\n", actual);
  77                         if (actual < bufsiz) {
  78                                 actual = read(infd, buffer, sizeof(buffer));
  79                                 bytes_read += actual;
  80                                 // confirm EOF condition
  81                                 test_long("EOF", actual, 0);
  82                                 dispatch_source_cancel(reader);
  83                                 dispatch_release(reader);
  84                         }
  85         });
  86
  87         dispatch_source_set_cancel_handler(reader, ^{
  88                 test_long("Bytes read", bytes_read, bytes_total);
  89                 int res = close(infd);
  90                 test_errno("close", res == -1 ? errno : 0, 0);
  91                 test_stop();
  92         });
  93
  94         dispatch_resume(reader);
  95
  96         dispatch_main();
  97 }