diff options
Diffstat (limited to 'usr.bin/tar/line_reader.c')
| -rw-r--r-- | usr.bin/tar/line_reader.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/usr.bin/tar/line_reader.c b/usr.bin/tar/line_reader.c new file mode 100644 index 0000000..c9df1b0 --- /dev/null +++ b/usr.bin/tar/line_reader.c @@ -0,0 +1,171 @@ +/*- + * Copyright (c) 2008 Tim Kientzle + * 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 + * in this position and unchanged. + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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 AUTHOR(S) 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. + */ + +#include "bsdtar_platform.h" +__FBSDID("$FreeBSD$"); + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "err.h" +#include "line_reader.h" + +#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(__BORLANDC__) +#define strdup _strdup +#endif + +/* + * Read lines from file and do something with each one. If option_null + * is set, lines are terminated with zero bytes; otherwise, they're + * terminated with newlines. + * + * This uses a self-sizing buffer to handle arbitrarily-long lines. + */ +struct lafe_line_reader { + FILE *f; + char *buff, *buff_end, *line_start, *line_end, *p; + char *pathname; + size_t buff_length; + int nullSeparator; /* Lines separated by null, not CR/CRLF/etc. */ + int ret; +}; + +struct lafe_line_reader * +lafe_line_reader(const char *pathname, int nullSeparator) +{ + struct lafe_line_reader *lr; + + lr = calloc(1, sizeof(*lr)); + if (lr == NULL) + bsdtar_errc(1, ENOMEM, "Can't open %s", pathname); + + lr->nullSeparator = nullSeparator; + lr->pathname = strdup(pathname); + + if (strcmp(pathname, "-") == 0) + lr->f = stdin; + else + lr->f = fopen(pathname, "r"); + if (lr->f == NULL) + bsdtar_errc(1, errno, "Couldn't open %s", pathname); + lr->buff_length = 8192; + lr->buff = malloc(lr->buff_length); + if (lr->buff == NULL) + bsdtar_errc(1, ENOMEM, "Can't read %s", pathname); + lr->line_start = lr->line_end = lr->buff_end = lr->buff; + + return (lr); +} + +const char * +lafe_line_reader_next(struct lafe_line_reader *lr) +{ + size_t bytes_wanted, bytes_read, new_buff_size; + char *line_start, *p; + + for (;;) { + /* If there's a line in the buffer, return it immediately. */ + while (lr->line_end < lr->buff_end) { + if (lr->nullSeparator) { + if (*lr->line_end == '\0') { + line_start = lr->line_start; + lr->line_start = lr->line_end + 1; + lr->line_end = lr->line_start; + return (line_start); + } + } else if (*lr->line_end == '\x0a' || *lr->line_end == '\x0d') { + *lr->line_end = '\0'; + line_start = lr->line_start; + lr->line_start = lr->line_end + 1; + lr->line_end = lr->line_start; + if (line_start[0] != '\0') + return (line_start); + } + lr->line_end++; + } + + /* If we're at end-of-file, process the final data. */ + if (lr->f == NULL) { + /* If there's more text, return one last line. */ + if (lr->line_end > lr->line_start) { + *lr->line_end = '\0'; + line_start = lr->line_start; + lr->line_start = lr->line_end + 1; + lr->line_end = lr->line_start; + return (line_start); + } + /* Otherwise, we're done. */ + return (NULL); + } + + /* Buffer only has part of a line. */ + if (lr->line_start > lr->buff) { + /* Move a leftover fractional line to the beginning. */ + memmove(lr->buff, lr->line_start, + lr->buff_end - lr->line_start); + lr->buff_end -= lr->line_start - lr->buff; + lr->line_end -= lr->line_start - lr->buff; + lr->line_start = lr->buff; + } else { + /* Line is too big; enlarge the buffer. */ + new_buff_size = lr->buff_length * 2; + if (new_buff_size <= lr->buff_length) + bsdtar_errc(1, ENOMEM, + "Line too long in %s", lr->pathname); + lr->buff_length = new_buff_size; + p = realloc(lr->buff, new_buff_size); + if (p == NULL) + bsdtar_errc(1, ENOMEM, + "Line too long in %s", lr->pathname); + lr->buff_end = p + (lr->buff_end - lr->buff); + lr->line_end = p + (lr->line_end - lr->buff); + lr->line_start = lr->buff = p; + } + + /* Get some more data into the buffer. */ + bytes_wanted = lr->buff + lr->buff_length - lr->buff_end; + bytes_read = fread(lr->buff_end, 1, bytes_wanted, lr->f); + lr->buff_end += bytes_read; + + if (ferror(lr->f)) + bsdtar_errc(1, errno, "Can't read %s", lr->pathname); + if (feof(lr->f)) { + if (lr->f != stdin) + fclose(lr->f); + lr->f = NULL; + } + } +} + +void +lafe_line_reader_free(struct lafe_line_reader *lr) +{ + free(lr->buff); + free(lr->pathname); + free(lr); +} |
