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  • /*
     * (C) Copyright 2011 Free Electrons
     * David Wagner <david.wagner@free-electrons.com>
     *
     * Inspired from envcrc.c:
     * (C) Copyright 2001
     * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
     *
     * See file CREDITS for list of people who contributed to this
     * project.
     *
     * This program is free software; you can redistribute it and/or
     * modify it under the terms of the GNU General Public License as
     * published by the Free Software Foundation; either version 2 of
     * the License, or (at your option) any later version.
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with this program; if not, write to the Free Software
     * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
     * MA 02111-1307 USA
     */
    
    
    /* We want the GNU version of basename() */
    #define _GNU_SOURCE
    
    
    #include <errno.h>
    #include <fcntl.h>
    #include <stdio.h>
    
    #include <stdint.h>
    #include <string.h>
    #include <unistd.h>
    
    #include <libgen.h>
    
    #include <sys/types.h>
    #include <sys/stat.h>
    
    #include "compiler.h"
    
    #include <version.h>
    
    
    #define CRC_SIZE sizeof(uint32_t)
    
    static void usage(const char *exec_name)
    {
    
    	fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
    
    	       "This tool takes a key=value input file (same as would a `printenv' show) and generates the corresponding environment image, ready to be flashed.\n"
    
    	       "\n"
    	       "\tThe input file is in format:\n"
    	       "\t\tkey1=value1\n"
    	       "\t\tkey2=value2\n"
    	       "\t\t...\n"
    	       "\t-r : the environment has multiple copies in flash\n"
    	       "\t-b : the target is big endian (default is little endian)\n"
    
    	       "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n"
    
    	       "\t-V : print version information and exit\n"
    
    	       "\n"
    	       "If the input file is \"-\", data is read from standard input\n",
    	       exec_name);
    }
    
    
    long int xstrtol(const char *s)
    {
    	long int tmp;
    
    	errno = 0;
    	tmp = strtol(s, NULL, 0);
    	if (!errno)
    		return tmp;
    
    	if (errno == ERANGE)
    		fprintf(stderr, "Bad integer format: %s\n",  s);
    	else
    		fprintf(stderr, "Error while parsing %s: %s\n", s,
    				strerror(errno));
    
    	exit(EXIT_FAILURE);
    }
    
    
    int main(int argc, char **argv)
    {
    	uint32_t crc, targetendian_crc;
    	const char *txt_filename = NULL, *bin_filename = NULL;
    	int txt_fd, bin_fd;
    	unsigned char *dataptr, *envptr;
    	unsigned char *filebuf = NULL;
    	unsigned int filesize = 0, envsize = 0, datasize = 0;
    	int bigendian = 0;
    	int redundant = 0;
    	unsigned char padbyte = 0xff;
    
    	int option;
    	int ret = EXIT_SUCCESS;
    
    	struct stat txt_file_stat;
    
    	int fp, ep;
    
    	const char *prg;
    
    	prg = basename(argv[0]);
    
    	/* Turn off getopt()'s internal error message */
    	opterr = 0;
    
    
    	while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
    
    			datasize = xstrtol(optarg);
    
    			break;
    		case 'o':
    			bin_filename = strdup(optarg);
    			if (!bin_filename) {
    
    				fprintf(stderr, "Can't strdup() the output filename\n");
    
    				return EXIT_FAILURE;
    			}
    			break;
    		case 'r':
    			redundant = 1;
    			break;
    		case 'b':
    			bigendian = 1;
    			break;
    		case 'p':
    
    			padbyte = xstrtol(optarg);
    
    		case 'V':
    			printf("%s version %s\n", prg, PLAIN_VERSION);
    			return EXIT_SUCCESS;
    
    		case ':':
    			fprintf(stderr, "Missing argument for option -%c\n",
    
    			usage(prg);
    
    			return EXIT_FAILURE;
    
    			fprintf(stderr, "Wrong option -%c\n", optopt);
    
    			return EXIT_FAILURE;
    		}
    	}
    
    	/* Check datasize and allocate the data */
    	if (datasize == 0) {
    
    		fprintf(stderr, "Please specify the size of the environment partition.\n");
    
    		return EXIT_FAILURE;
    	}
    
    	dataptr = malloc(datasize * sizeof(*dataptr));
    	if (!dataptr) {
    
    		fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
    				datasize);
    
    		return EXIT_FAILURE;
    	}
    
    	/*
    	 * envptr points to the beginning of the actual environment (after the
    
    	 * crc and possible `redundant' byte
    
    	 */
    	envsize = datasize - (CRC_SIZE + redundant);
    	envptr = dataptr + CRC_SIZE + redundant;
    
    	/* Pad the environment with the padding byte */
    	memset(envptr, padbyte, envsize);
    
    	/* Open the input file ... */
    
    	if (optind >= argc || strcmp(argv[optind], "-") == 0) {
    
    		int readlen = sizeof(*envptr) * 4096;
    
    		txt_fd = STDIN_FILENO;
    
    		do {
    			filebuf = realloc(filebuf, readlen);
    
    			if (!filebuf) {
    				fprintf(stderr, "Can't realloc memory for the input file buffer\n");
    				return EXIT_FAILURE;
    			}
    
    			readbytes = read(txt_fd, filebuf + filesize, readlen);
    
    			if (errno) {
    				fprintf(stderr, "Error while reading stdin: %s\n",
    						strerror(errno));
    				return EXIT_FAILURE;
    			}
    
    			filesize += readbytes;
    		} while (readbytes == readlen);
    
    	} else {
    
    		txt_fd = open(txt_filename, O_RDONLY);
    		if (txt_fd == -1) {
    			fprintf(stderr, "Can't open \"%s\": %s\n",
    					txt_filename, strerror(errno));
    			return EXIT_FAILURE;
    		}
    		/* ... and check it */
    		ret = fstat(txt_fd, &txt_file_stat);
    		if (ret == -1) {
    
    			fprintf(stderr, "Can't stat() on \"%s\": %s\n",
    					txt_filename, strerror(errno));
    
    			return EXIT_FAILURE;
    		}
    
    		filesize = txt_file_stat.st_size;
    
    
    		filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
    			       MAP_PRIVATE, txt_fd, 0);
    		if (filebuf == MAP_FAILED) {
    
    			fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
    
    					sizeof(*envptr) * filesize,
    					strerror(errno));
    			fprintf(stderr, "Falling back to read()\n");
    
    			filebuf = malloc(sizeof(*envptr) * filesize);
    			ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
    			if (ret != sizeof(*envptr) * filesize) {
    
    				fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
    
    					sizeof(*envptr) * filesize,
    					strerror(errno));
    
    				return EXIT_FAILURE;
    			}
    
    	/* The +1 is for the additionnal ending \0. See below. */
    	if (filesize + 1 > envsize) {
    		fprintf(stderr, "The input file is larger than the environment partition size\n");
    
    		return EXIT_FAILURE;
    	}
    
    	/* Replace newlines separating variables with \0 */
    	for (fp = 0, ep = 0 ; fp < filesize ; fp++) {
    		if (filebuf[fp] == '\n') {
    
    				 * Newlines at the beginning of the file ?
    				 * Ignore them.
    
    				 */
    				continue;
    			} else if (filebuf[fp-1] == '\\') {
    				/*
    				 * Embedded newline in a variable.
    				 *
    
    				 * The backslash was added to the envptr; rewind
    				 * and replace it with a newline
    
    				 */
    				ep--;
    				envptr[ep++] = '\n';
    			} else {
    				/* End of a variable */
    				envptr[ep++] = '\0';
    			}
    		} else {
    			envptr[ep++] = filebuf[fp];
    		}
    	}
    	/*
    	 * Make sure there is a final '\0'
    	 * And do it again on the next byte to mark the end of the environment.
    	 */
    	if (envptr[ep-1] != '\0') {
    		envptr[ep++] = '\0';
    		/*
    		 * The text file doesn't have an ending newline.  We need to
    		 * check the env size again to make sure we have room for two \0
    		 */
    		if (ep >= envsize) {
    
    			fprintf(stderr, "The environment file is too large for the target environment storage\n");
    
    			return EXIT_FAILURE;
    		}
    		envptr[ep] = '\0';
    	} else {
    		envptr[ep] = '\0';
    	}
    
    	/* Computes the CRC and put it at the beginning of the data */
    	crc = crc32(0, envptr, envsize);
    	targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
    
    
    	memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
    	if (redundant)
    		dataptr[sizeof(targetendian_crc)] = 1;
    
    	if (!bin_filename || strcmp(bin_filename, "-") == 0) {
    		bin_fd = STDOUT_FILENO;
    	} else {
    
    		bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
    					     S_IWGRP);
    
    		if (bin_fd == -1) {
    			fprintf(stderr, "Can't open output file \"%s\": %s\n",
    					bin_filename, strerror(errno));
    			return EXIT_FAILURE;
    		}
    
    	}
    
    	if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
    			sizeof(*dataptr) * datasize) {
    		fprintf(stderr, "write() failed: %s\n", strerror(errno));
    		return EXIT_FAILURE;
    	}
    
    	ret = close(bin_fd);
    
    	return ret;
    }