freebsd-dev/usr.bin/grep/file.c

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/* $NetBSD: file.c,v 1.5 2011/02/16 18:35:39 joerg Exp $ */
/* $FreeBSD$ */
/* $OpenBSD: file.c,v 1.11 2010/07/02 20:48:48 nicm Exp $ */
/*-
2010-08-19 09:28:59 +00:00
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.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 <zlib.h>
#ifndef WITHOUT_LZMA
#include <lzma.h>
#endif
#ifndef WITHOUT_BZIP2
#include <bzlib.h>
#endif
#include "grep.h"
#define MAXBUFSIZ (32 * 1024)
#define LNBUFBUMP 80
static gzFile gzbufdesc;
#ifndef WITHOUT_LZMA
static lzma_stream lstrm = LZMA_STREAM_INIT;
static lzma_action laction;
static uint8_t lin_buf[MAXBUFSIZ];
#endif
#ifndef WITHOUT_BZIP2
static BZFILE* bzbufdesc;
#endif
static unsigned char *buffer;
static unsigned char *bufpos;
static size_t bufrem;
static size_t fsiz;
static unsigned char *lnbuf;
static size_t lnbuflen;
static inline int
grep_refill(struct file *f)
{
ssize_t nr;
if (filebehave == FILE_MMAP)
return (0);
bufpos = buffer;
bufrem = 0;
if (filebehave == FILE_GZIP) {
nr = gzread(gzbufdesc, buffer, MAXBUFSIZ);
#ifndef WITHOUT_BZIP2
} else if (filebehave == FILE_BZIP && bzbufdesc != NULL) {
int bzerr;
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;
}
#endif
#ifndef WITHOUT_LZMA
} else if ((filebehave == FILE_XZ) || (filebehave == FILE_LZMA)) {
lzma_ret ret;
lstrm.next_out = buffer;
do {
if (lstrm.avail_in == 0) {
lstrm.next_in = lin_buf;
nr = read(f->fd, lin_buf, MAXBUFSIZ);
if (nr < 0)
return (-1);
else if (nr == 0)
laction = LZMA_FINISH;
lstrm.avail_in = nr;
}
ret = lzma_code(&lstrm, laction);
if (ret != LZMA_OK && ret != LZMA_STREAM_END)
return (-1);
if (lstrm.avail_out == 0 || ret == LZMA_STREAM_END) {
bufrem = MAXBUFSIZ - lstrm.avail_out;
lstrm.next_out = buffer;
lstrm.avail_out = MAXBUFSIZ;
}
} while (bufrem == 0 && ret != LZMA_STREAM_END);
return (0);
#endif /* WIHTOUT_LZMA */
} else
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 (bufpos);
}
/* Look for a newline in the remaining part of the buffer */
if ((p = memchr(bufpos, '\n', bufrem)) != NULL) {
++p; /* advance over newline */
ret = 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, '\n', 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 (lnbuf);
error:
*lenp = 0;
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)
goto error1;
if (filebehave == FILE_MMAP) {
struct stat st;
if ((fstat(f->fd, &st) == -1) || (st.st_size > OFF_MAX) ||
(!S_ISREG(st.st_mode)))
filebehave = FILE_STDIO;
else {
int flags = MAP_PRIVATE | MAP_NOCORE | MAP_NOSYNC;
#ifdef MAP_PREFAULT_READ
flags |= MAP_PREFAULT_READ;
#endif
fsiz = st.st_size;
buffer = mmap(NULL, fsiz, PROT_READ, flags,
f->fd, (off_t)0);
if (buffer == MAP_FAILED)
filebehave = FILE_STDIO;
else {
bufrem = st.st_size;
bufpos = buffer;
madvise(buffer, st.st_size, MADV_SEQUENTIAL);
}
}
}
if ((buffer == NULL) || (buffer == MAP_FAILED))
buffer = grep_malloc(MAXBUFSIZ);
if (filebehave == FILE_GZIP &&
(gzbufdesc = gzdopen(f->fd, "r")) == NULL)
goto error2;
#ifndef WITHOUT_BZIP2
if (filebehave == FILE_BZIP &&
(bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL)
goto error2;
#endif
#ifndef WITHOUT_LZMA
else if ((filebehave == FILE_XZ) || (filebehave == FILE_LZMA)) {
lzma_ret ret;
ret = (filebehave == FILE_XZ) ?
lzma_stream_decoder(&lstrm, UINT64_MAX,
LZMA_CONCATENATED) :
lzma_alone_decoder(&lstrm, UINT64_MAX);
if (ret != LZMA_OK)
goto error2;
lstrm.avail_in = 0;
lstrm.avail_out = MAXBUFSIZ;
laction = LZMA_RUN;
}
#endif
/* Fill read buffer, also catches errors early */
if (bufrem == 0 && grep_refill(f) != 0)
goto error2;
/* Check for binary stuff, if necessary */
if (binbehave != BINFILE_TEXT && memchr(bufpos, '\0', bufrem) != NULL)
f->binary = true;
return (f);
error2:
close(f->fd);
error1:
free(f);
return (NULL);
}
/*
* Closes a file.
*/
void
grep_close(struct file *f)
{
close(f->fd);
/* Reset read buffer and line buffer */
if (filebehave == FILE_MMAP) {
munmap(buffer, fsiz);
buffer = NULL;
}
bufpos = buffer;
bufrem = 0;
free(lnbuf);
lnbuf = NULL;
lnbuflen = 0;
}