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-rw-r--r--usr.bin/grep/mmfile.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/usr.bin/grep/mmfile.c b/usr.bin/grep/mmfile.c
new file mode 100644
index 0000000..62d089a
--- /dev/null
+++ b/usr.bin/grep/mmfile.c
@@ -0,0 +1,90 @@
+/* $OpenBSD: mmfile.c,v 1.19 2019/01/27 14:43:09 deraadt Exp $ */
+
+/*-
+ * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
+ * 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/mman.h>
+#include <sys/stat.h>
+
+#include <err.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "grep.h"
+
+#ifndef SMALL
+
+#define MAX_MAP_LEN 1048576
+
+mmf_t *
+mmopen(int fd, struct stat *st)
+{
+ mmf_t *mmf;
+
+ mmf = grep_malloc(sizeof *mmf);
+ if (st->st_size > SIZE_MAX) /* too big to mmap */
+ goto ouch;
+ mmf->len = (size_t)st->st_size;
+ mmf->fd = fd;
+ mmf->base = mmap(NULL, mmf->len, PROT_READ, MAP_PRIVATE, mmf->fd, (off_t)0);
+ if (mmf->base == MAP_FAILED)
+ goto ouch;
+ mmf->ptr = mmf->base;
+ mmf->end = mmf->base + mmf->len;
+ madvise(mmf->base, mmf->len, MADV_SEQUENTIAL);
+ return mmf;
+
+ouch:
+ free(mmf);
+ return NULL;
+}
+
+void
+mmclose(mmf_t *mmf)
+{
+ munmap(mmf->base, mmf->len);
+ close(mmf->fd);
+ free(mmf);
+}
+
+char *
+mmfgetln(mmf_t *mmf, size_t *l)
+{
+ static char *p;
+
+ if (mmf->ptr >= mmf->end)
+ return NULL;
+ for (p = mmf->ptr; mmf->ptr < mmf->end; ++mmf->ptr)
+ if (*mmf->ptr == '\n')
+ break;
+
+ *l = mmf->ptr - p;
+ ++mmf->ptr;
+ return p;
+}
+
+#endif