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 #include <mem/memory_utils.h> 34 35 36 37 /* Minimum pipe region size in pages. */ 38 39 const unsigned int PIPE_PAGES = 2; 40 41 /* Use the writer to fill the pipe with data. */ 42 43 static void write_pipe(file_t *writer, int number) 44 { 45 offset_t size = 600; 46 char buffer[size]; 47 long err; 48 49 /* Make writers blocking to permit synchronisation. */ 50 51 if ((err = client_set_blocking(writer, NOTIFY_SPACE_AVAILABLE))) 52 { 53 printf("Could not set pipe #%d as blocking: %s\n", number, l4sys_errtostr(err)); 54 return; 55 } 56 57 for (int loop = 0; loop < 3; loop++) 58 { 59 for (int region = 0; region < 26; region++) 60 { 61 memset(buffer, (int) 'a' + region, size); 62 63 offset_t nwritten = client_write(writer, buffer, size); 64 65 printf("Written %ld/%ld in #%d of %d/%d to pipe #%d...\n", nwritten, size, region, loop, 2, number); 66 } 67 68 sleep(1); 69 } 70 71 /* Flush to make the final output available. */ 72 73 client_flush(writer); 74 75 client_close(writer); 76 } 77 78 /* Use the reader to obtain data from the pipe. */ 79 80 static void read_pipes(file_t *reader1, file_t *reader2) 81 { 82 offset_t size = 600, totals[] = {0, 0}; 83 unsigned int active = 2; 84 long err; 85 file_t *reader; 86 87 /* Register the readers for notification. */ 88 89 // NOTE: Use the flags to detect initial conditions! 90 91 if ((err = client_subscribe(reader1, NOTIFY_CONTENT_AVAILABLE | NOTIFY_PEER_CLOSED)) || 92 (err = client_subscribe(reader2, NOTIFY_CONTENT_AVAILABLE | NOTIFY_PEER_CLOSED))) 93 { 94 printf("Could not subscribe to notifications: %s\n", l4sys_errtostr(err)); 95 return; 96 } 97 98 while (1) 99 { 100 char buffer[size]; 101 offset_t nread; 102 103 /* Wait for notification of content. */ 104 105 err = client_wait_files(&reader); 106 107 if (err) 108 { 109 printf("Error waiting for notifications: %s\n", l4sys_errtostr(err)); 110 return; 111 } 112 113 if ((reader != reader1) && (reader != reader2)) 114 { 115 printf("Spurious notification received for %p versus %p, %p.\n", reader, reader1, reader2); 116 continue; 117 } 118 119 int p = reader == reader1 ? 0 : 1; 120 121 printf("Pipe #%d notified with conditions:%s%s\n", p, reader->notifications & NOTIFY_PEER_CLOSED ? " closed" : "", 122 reader->notifications & NOTIFY_CONTENT_AVAILABLE ? " content" : ""); 123 124 nread = client_read(reader, buffer, size); 125 126 while (nread) 127 { 128 totals[p] += nread; 129 130 printf("Read %ld/%ld, total %ld, first %c, last %c, from pipe #%d...\n", nread, size, totals[p], *buffer, *(buffer + nread - 1), p + 1); 131 #if 0 132 for (offset_t i = 0; i < nread; i += 60) 133 { 134 fwrite(buffer + i, sizeof(char), nread - i > 60 ? 60 : nread - i, stdout); 135 fputs("\n", stdout); 136 } 137 #endif 138 nread = client_read(reader, buffer, size); 139 } 140 141 /* Without any more content, a peer closed event should terminate reading 142 from the pipe. */ 143 144 if (reader->notifications & NOTIFY_PEER_CLOSED) 145 { 146 active--; 147 if (!active) 148 break; 149 } 150 } 151 152 client_close(reader1); 153 client_close(reader2); 154 155 printf("Data shown.\n"); 156 } 157 158 int main(void) 159 { 160 /* Invoke the open method to receive the pipe endpoint references. */ 161 162 file_t *reader1, *reader2, *writer1, *writer2; 163 long err = client_pipe(&reader1, &writer1) || client_pipe(&reader2, &writer2); 164 165 if (err) 166 { 167 printf("Could not obtain pipes: %s\n", l4sys_errtostr(err)); 168 return 1; 169 } 170 171 /* Schedule reader and writer threads. */ 172 173 std::thread *activities[3]; 174 175 activities[0] = new std::thread(read_pipes, reader1, reader2); 176 activities[1] = new std::thread(write_pipe, writer1, 1); 177 activities[2] = new std::thread(write_pipe, writer2, 2); 178 179 for (int i = 0; i < 3; i++) 180 activities[i]->join(); 181 } 182 183 // vim: tabstop=2 expandtab shiftwidth=2