diff options
Diffstat (limited to 'usr.bin/grep/file.c')
| -rw-r--r-- | usr.bin/grep/file.c | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/usr.bin/grep/file.c b/usr.bin/grep/file.c new file mode 100644 index 0000000..ef057ba --- /dev/null +++ b/usr.bin/grep/file.c @@ -0,0 +1,276 @@ +/* $NetBSD: file.c,v 1.10 2018/08/12 09:03:21 christos Exp $ */ +/* $FreeBSD: head/usr.bin/grep/file.c 211496 2010-08-19 09:28:59Z des $ */ +/* $OpenBSD: file.c,v 1.11 2010/07/02 20:48:48 nicm Exp $ */ + +/*- + * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav + * Copyright (C) 2008-2010 Gabor Kovesdan <gabor@FreeBSD.org> + * Copyright (C) 2010 Dimitry Andric <dimitry@andric.com> + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + */ + +#if HAVE_NBTOOL_CONFIG_H +#include "nbtool_config.h" +#endif + +#include <sys/cdefs.h> +__RCSID("$NetBSD: file.c,v 1.10 2018/08/12 09:03:21 christos Exp $"); + +#include <sys/param.h> +#include <sys/types.h> +#include <sys/stat.h> + +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <stddef.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <wchar.h> +#include <wctype.h> + +#include "grep.h" + +#define MAXBUFSIZ (32 * 1024) +#define LNBUFBUMP 80 + +#ifndef WITHOUT_GZIP +static gzFile gzbufdesc; +#endif +#ifndef WITHOUT_BZ2 +static BZFILE* bzbufdesc; +#endif + +static unsigned char buffer[MAXBUFSIZ]; +static unsigned char *bufpos; +static size_t bufrem; + +static unsigned char *lnbuf; +static size_t lnbuflen; + +static inline int +grep_refill(struct file *f) +{ + ssize_t nr = -1; + int bzerr; + + bufpos = buffer; + bufrem = 0; + +#ifndef WITHOUT_GZIP + if (filebehave == FILE_GZIP) { + nr = gzread(gzbufdesc, buffer, MAXBUFSIZ); + if (nr == -1) + return -1; + } +#endif +#ifndef WITHOUT_BZ2 + if (filebehave == FILE_BZIP && bzbufdesc != NULL) { + nr = BZ2_bzRead(&bzerr, bzbufdesc, buffer, MAXBUFSIZ); + switch (bzerr) { + case BZ_OK: + case BZ_STREAM_END: + /* No problem, nr will be okay */ + break; + case BZ_DATA_ERROR_MAGIC: + /* + * As opposed to gzread(), which simply returns the + * plain file data, if it is not in the correct + * compressed format, BZ2_bzRead() instead aborts. + * + * So, just restart at the beginning of the file again, + * and use plain reads from now on. + */ + BZ2_bzReadClose(&bzerr, bzbufdesc); + bzbufdesc = NULL; + if (lseek(f->fd, 0, SEEK_SET) == -1) + return (-1); + nr = read(f->fd, buffer, MAXBUFSIZ); + break; + default: + /* Make sure we exit with an error */ + nr = -1; + } + if (nr == -1) + return -1; + } +#endif + if (nr == -1) { + nr = read(f->fd, buffer, MAXBUFSIZ); + } + + if (nr < 0) + return (-1); + + bufrem = nr; + return (0); +} + +static inline int +grep_lnbufgrow(size_t newlen) +{ + + if (lnbuflen < newlen) { + lnbuf = grep_realloc(lnbuf, newlen); + lnbuflen = newlen; + } + + return (0); +} + +char * +grep_fgetln(struct file *f, size_t *lenp) +{ + unsigned char *p; + char *ret; + size_t len; + size_t off; + ptrdiff_t diff; + + /* Fill the buffer, if necessary */ + if (bufrem == 0 && grep_refill(f) != 0) + goto error; + + if (bufrem == 0) { + /* Return zero length to indicate EOF */ + *lenp = 0; + return ((char *)bufpos); + } + + /* Look for a newline in the remaining part of the buffer */ + if ((p = memchr(bufpos, line_sep, bufrem)) != NULL) { + ++p; /* advance over newline */ + ret = (char *)bufpos; + len = p - bufpos; + bufrem -= len; + bufpos = p; + *lenp = len; + return (ret); + } + + /* We have to copy the current buffered data to the line buffer */ + for (len = bufrem, off = 0; ; len += bufrem) { + /* Make sure there is room for more data */ + if (grep_lnbufgrow(len + LNBUFBUMP)) + goto error; + memcpy(lnbuf + off, bufpos, len - off); + off = len; + if (grep_refill(f) != 0) + goto error; + if (bufrem == 0) + /* EOF: return partial line */ + break; + if ((p = memchr(bufpos, line_sep, bufrem)) == NULL) + continue; + /* got it: finish up the line (like code above) */ + ++p; + diff = p - bufpos; + len += diff; + if (grep_lnbufgrow(len)) + goto error; + memcpy(lnbuf + off, bufpos, diff); + bufrem -= diff; + bufpos = p; + break; + } + *lenp = len; + return ((char *)lnbuf); + +error: + *lenp = 0; + return (NULL); +} + +static inline struct file * +grep_file_init(struct file *f) +{ + +#ifndef WITHOUT_GZIP + if (filebehave == FILE_GZIP && + (gzbufdesc = gzdopen(f->fd, "r")) == NULL) + goto error; +#endif + +#ifndef WITHOUT_BZ2 + if (filebehave == FILE_BZIP && + (bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL) + goto error; +#endif + + /* Fill read buffer, also catches errors early */ + if (grep_refill(f) != 0) + goto error; + + /* Check for binary stuff, if necessary */ + if (!nulldataflag && binbehave != BINFILE_TEXT && + memchr(bufpos, '\0', bufrem) != NULL) + f->binary = true; + + return (f); +error: + close(f->fd); + free(f); + return (NULL); +} + +/* + * Opens a file for processing. + */ +struct file * +grep_open(const char *path) +{ + struct file *f; + + f = grep_malloc(sizeof *f); + memset(f, 0, sizeof *f); + if (path == NULL) { + /* Processing stdin implies --line-buffered. */ + lbflag = true; + f->fd = STDIN_FILENO; + } else if ((f->fd = open(path, O_RDONLY)) == -1) { + free(f); + return (NULL); + } + + return (grep_file_init(f)); +} + +/* + * Closes a file. + */ +void +grep_close(struct file *f) +{ + + close(f->fd); + + /* Reset read buffer and line buffer */ + bufpos = buffer; + bufrem = 0; + + free(lnbuf); + lnbuf = NULL; + lnbuflen = 0; +} |