1 /* 2 * Test pipe operations. 3 * 4 * Copyright (C) 2020, 2021 Paul Boddie <paul@boddie.org.uk> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 * Boston, MA 02110-1301, USA 20 */ 21 22 #include <l4/re/env.h> 23 #include <l4/sys/err.h> 24 25 #include <thread> 26 27 #include <stdio.h> 28 #include <string.h> 29 #include <stdlib.h> 30 #include <unistd.h> /* sleep */ 31 32 #include <fsclient/client.h> 33 34 35 36 /* Use the writer to fill the pipe with data. */ 37 38 static void write_pipe(file_t *writer, int number) 39 { 40 offset_t size = 600; 41 char buffer[size]; 42 long err; 43 44 /* Make writers blocking to permit synchronisation. */ 45 46 if ((err = client_set_blocking(writer, NOTIFY_SPACE_AVAILABLE))) 47 { 48 printf("Could not set pipe #%d as blocking: %s\n", number, l4sys_errtostr(err)); 49 return; 50 } 51 52 for (int loop = 0; loop < 3; loop++) 53 { 54 for (int region = 0; region < 26; region++) 55 { 56 memset(buffer, (int) 'a' + region, size); 57 58 offset_t nwritten = client_write(writer, buffer, size); 59 60 printf("Written %ld/%ld in #%d of %d/%d to pipe #%d...\n", nwritten, size, region, loop, 2, number); 61 } 62 63 sleep(1); 64 } 65 66 /* Flush to make the final output available. */ 67 68 client_close(writer); 69 } 70 71 /* Use the reader to obtain data from the pipe. */ 72 73 static void read_pipes(file_t *reader1, file_t *reader2) 74 { 75 offset_t size = 600, totals[] = {0, 0}; 76 unsigned int active = 2; 77 long err; 78 file_t *reader; 79 80 /* Register the readers for notification. */ 81 82 if ((err = client_subscribe(reader1, NOTIFY_CONTENT_AVAILABLE | NOTIFY_PEER_CLOSED)) || 83 (err = client_subscribe(reader2, NOTIFY_CONTENT_AVAILABLE | NOTIFY_PEER_CLOSED))) 84 { 85 printf("Could not subscribe to notifications: %s\n", l4sys_errtostr(err)); 86 return; 87 } 88 89 while (1) 90 { 91 char buffer[size]; 92 offset_t nread; 93 94 /* Wait for notification of content. */ 95 96 err = client_wait_files(&reader); 97 98 if (err) 99 { 100 printf("Error waiting for notifications: %s\n", l4sys_errtostr(err)); 101 return; 102 } 103 104 if ((reader != reader1) && (reader != reader2)) 105 { 106 printf("Spurious notification received for %p versus %p, %p.\n", reader, reader1, reader2); 107 continue; 108 } 109 110 int p = reader == reader1 ? 0 : 1; 111 112 printf("Pipe #%d notified with conditions:%s%s\n", p + 1, reader->notifications & NOTIFY_PEER_CLOSED ? " closed" : "", 113 reader->notifications & NOTIFY_CONTENT_AVAILABLE ? " content" : ""); 114 115 nread = client_read(reader, buffer, size); 116 117 while (nread) 118 { 119 totals[p] += nread; 120 121 printf("Read %ld/%ld, total %ld, first %c, last %c, from pipe #%d...\n", nread, size, totals[p], *buffer, *(buffer + nread - 1), p + 1); 122 #if 0 123 for (offset_t i = 0; i < nread; i += 60) 124 { 125 fwrite(buffer + i, sizeof(char), nread - i > 60 ? 60 : nread - i, stdout); 126 fputs("\n", stdout); 127 } 128 #endif 129 nread = client_read(reader, buffer, size); 130 } 131 132 /* Without any more content, a peer closed event should terminate reading 133 from the pipe. */ 134 135 if (reader->notifications & NOTIFY_PEER_CLOSED) 136 { 137 active--; 138 if (!active) 139 break; 140 } 141 } 142 143 client_close(reader1); 144 client_close(reader2); 145 146 printf("Data shown.\n"); 147 } 148 149 int main(void) 150 { 151 /* Invoke the open method to receive the pipe endpoint references. */ 152 153 file_t *reader1, *reader2, *writer1, *writer2; 154 long err = client_pipe(&reader1, &writer1) || client_pipe(&reader2, &writer2); 155 156 if (err) 157 { 158 printf("Could not obtain pipes: %s\n", l4sys_errtostr(err)); 159 return 1; 160 } 161 162 /* Schedule reader and writer threads. */ 163 164 std::thread *activities[3]; 165 166 activities[0] = new std::thread(read_pipes, reader1, reader2); 167 activities[1] = new std::thread(write_pipe, writer1, 1); 168 activities[2] = new std::thread(write_pipe, writer2, 2); 169 170 for (int i = 0; i < 3; i++) 171 activities[i]->join(); 172 } 173 174 // vim: tabstop=2 expandtab shiftwidth=2