diff --git a/examples/sky/example-coffee.c b/examples/sky/example-coffee.c new file mode 100644 index 000000000..ee77849e4 --- /dev/null +++ b/examples/sky/example-coffee.c @@ -0,0 +1,182 @@ +/* + * Copyright (c) 2011, Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * This file is part of the Contiki operating system. + */ + +/** + * \file + * Example on how to use CFS/Coffee. + * \author + * Nicolas Tsiftes + */ + +#include + +#include "contiki.h" +#include "cfs/cfs.h" +#include "cfs/cfs-coffee.h" + +PROCESS(example_coffee_process, "Coffee example"); +AUTOSTART_PROCESSES(&example_coffee_process); + +#define FILENAME "test" + +/* Formatting is needed if the storage device is in an unknown state; + e.g., when using Coffee on the storage device for the first time. */ +#ifndef NEED_FORMATTING +#define NEED_FORMATTING 0 +#endif + +static int +file_test(const char *filename, char *msg) +{ + static uint8_t sequence; + int fd; + int r; + struct record { + char message[16]; + uint8_t sequence; + } record; + + /* + * Coffee determines the file length by finding the last non-zero byte + * of the file. This I/O semantic requires that each record should end + * with a non-zero, if we are writing multiple records and closing the + * file descriptor in between. + * + * In this example, in which the file_test function can be called + * multiple times, we ensure that the sequence counter starts at 1. + */ + + if(sequence == 255) { + /* No more sequence numbers available. */ + return -1; + } + sequence++; + + strncpy(record.message, msg, sizeof(record.message) - 1); + record.message[sizeof(record.message) - 1] = '\0'; + record.sequence = sequence; + + /* Obtain a file descriptor for the file, capable of handling both + reads and writes. */ + fd = cfs_open(FILENAME, CFS_WRITE | CFS_APPEND | CFS_READ); + if(fd < 0) { + printf("failed to open %s\n", FILENAME); + return 0; + } + + r = cfs_write(fd, &record, sizeof(record)); + if(r != sizeof(record)) { + printf("failed to write %d bytes to %s\n", + (int)sizeof(record), FILENAME); + cfs_close(fd); + return 0; + } + + printf("Wrote message \"%s\", sequence %u\n", + record.message, record.sequence); + + /* To read back the message, we need to move the file pointer to the + beginning of the file. */ + if(cfs_seek(fd, 0, CFS_SEEK_SET) != 0) { + printf("seek failed\n"); + cfs_close(fd); + return 0; + } + + /* Read all written records and print their contents. */ + for(;;) { + r = cfs_read(fd, &record, sizeof(record)); + if(r == 0) { + break; + } else if(r < sizeof(record)) { + printf("failed to read %d bytes from %s, got %d\n", + (int)sizeof(record), FILENAME, r); + cfs_close(fd); + return 0; + } + + printf("Read message \"%s\", sequence %u\n", + record.message, record.sequence); + } + + /* Release the internal resources held by Coffee for + the file descriptor. */ + cfs_close(fd); + + return 1; +} + +static int +dir_test(void) +{ + struct cfs_dir dir; + struct cfs_dirent dirent; + + /* Coffee provides a root directory only. */ + if(cfs_opendir(&dir, "/") != 0) { + printf("failed to open the root directory\n"); + return 0; + } + + /* List all files and their file sizes. */ + printf("Available files\n"); + while(cfs_readdir(&dir, &dirent) == 0) { + printf("%s (%lu bytes)\n", dirent.name, (unsigned long)dirent.size); + } + + cfs_closedir(&dir); + + return 1; +} + +PROCESS_THREAD(example_coffee_process, ev, data) +{ + PROCESS_BEGIN(); + +#if NEED_FORMATTING + cfs_coffee_format(); +#endif + + /* Ensure that we will be working with a new file. */ + cfs_remove(FILENAME); + + if(file_test(FILENAME, "The first test") == 0) { + printf("file test 1 failed\n"); + } + if(file_test(FILENAME, "The second test") == 0) { + printf("file test 2 failed\n"); + } + if(dir_test() == 0) { + printf("dir test failed\n"); + } + + PROCESS_END(); +}