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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 17:00:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 17:00:10 +0000
commit1ebbd027274333758fc3517685d81847601db676 (patch)
tree5259d053d3e3066e0745150805fa4b20184eef98 /src/buffer.c
parentInitial commit. (diff)
downloadfile-1ebbd027274333758fc3517685d81847601db676.tar.xz
file-1ebbd027274333758fc3517685d81847601db676.zip
Adding upstream version 1:5.45.upstream/1%5.45upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/buffer.c')
-rw-r--r--src/buffer.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/src/buffer.c b/src/buffer.c
new file mode 100644
index 0000000..598db14
--- /dev/null
+++ b/src/buffer.c
@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) Christos Zoulas 2017.
+ * 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 immediately at the beginning of the file, without modification,
+ * 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 "file.h"
+
+#ifndef lint
+FILE_RCSID("@(#)$File: buffer.c,v 1.13 2023/07/02 12:48:39 christos Exp $")
+#endif /* lint */
+
+#include "magic.h"
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+
+void
+buffer_init(struct buffer *b, int fd, const struct stat *st, const void *data,
+ size_t len)
+{
+ b->fd = fd;
+ if (st)
+ memcpy(&b->st, st, sizeof(b->st));
+ else if (b->fd == -1 || fstat(b->fd, &b->st) == -1)
+ memset(&b->st, 0, sizeof(b->st));
+ b->fbuf = data;
+ b->flen = len;
+ b->eoff = 0;
+ b->ebuf = NULL;
+ b->elen = 0;
+}
+
+void
+buffer_fini(struct buffer *b)
+{
+ free(b->ebuf);
+ b->ebuf = NULL;
+ b->elen = 0;
+}
+
+int
+buffer_fill(const struct buffer *bb)
+{
+ struct buffer *b = CCAST(struct buffer *, bb);
+
+ if (b->elen != 0)
+ return b->elen == FILE_BADSIZE ? -1 : 0;
+
+ if (!S_ISREG(b->st.st_mode))
+ goto out;
+
+ b->elen = CAST(size_t, b->st.st_size) < b->flen ?
+ CAST(size_t, b->st.st_size) : b->flen;
+ if (b->elen == 0) {
+ free(b->ebuf);
+ b->ebuf = NULL;
+ return 0;
+ }
+ if ((b->ebuf = malloc(b->elen)) == NULL)
+ goto out;
+
+ b->eoff = b->st.st_size - b->elen;
+ if (pread(b->fd, b->ebuf, b->elen, b->eoff) == -1) {
+ free(b->ebuf);
+ b->ebuf = NULL;
+ goto out;
+ }
+
+ return 0;
+out:
+ b->elen = FILE_BADSIZE;
+ return -1;
+}