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authorDan Willemsen <dwillemsen@google.com>2022-03-29 01:18:04 -0700
committerDan Willemsen <dwillemsen@google.com>2022-03-29 01:19:29 -0700
commit24d5d8d1665f31b911b52d961938a1737f957c10 (patch)
tree4159a2dcfc6eb4837fb6732f78e23d70d3f270c9 /tests/read-file.c
parenta41dd3ba30d74cdaa946f453d0fe4035c3e2575d (diff)
downloadm4-24d5d8d1665f31b911b52d961938a1737f957c10.tar.gz
Upgrade to v1.4.19: replace contents with tarball
This preserves the Android-specific files, but replaces everything else with the contents of the 1.4.19 tarball. The METADATA update is the only change for the Android files, other updates will come in later changes. Change-Id: I9699b0fe119e7542e17497da8e4a11380b78867e
Diffstat (limited to 'tests/read-file.c')
-rw-r--r--tests/read-file.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/tests/read-file.c b/tests/read-file.c
new file mode 100644
index 0000000..3c581dc
--- /dev/null
+++ b/tests/read-file.c
@@ -0,0 +1,216 @@
+/* read-file.c -- read file contents into a string
+ Copyright (C) 2006, 2009-2021 Free Software Foundation, Inc.
+ Written by Simon Josefsson and Bruno Haible.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include "read-file.h"
+
+/* Get fstat. */
+#include <sys/stat.h>
+
+/* Get ftello. */
+#include <stdio.h>
+
+/* Get PTRDIFF_MAX. */
+#include <stdint.h>
+
+/* Get malloc, realloc, free. */
+#include <stdlib.h>
+
+/* Get explicit_bzero, memcpy. */
+#include <string.h>
+
+/* Get errno. */
+#include <errno.h>
+
+/* Read a STREAM and return a newly allocated string with the content,
+ and set *LENGTH to the length of the string. The string is
+ zero-terminated, but the terminating zero byte is not counted in
+ *LENGTH. On errors, *LENGTH is undefined, errno preserves the
+ values set by system functions (if any), and NULL is returned.
+
+ If the RF_SENSITIVE flag is set in FLAGS:
+ - You should control the buffering of STREAM using 'setvbuf'. Either
+ clear the buffer of STREAM after closing it, or disable buffering of
+ STREAM before calling this function.
+ - The memory buffer internally allocated will be cleared upon failure. */
+char *
+fread_file (FILE *stream, int flags, size_t *length)
+{
+ char *buf = NULL;
+ size_t alloc = BUFSIZ;
+
+ /* For a regular file, allocate a buffer that has exactly the right
+ size. This avoids the need to do dynamic reallocations later. */
+ {
+ struct stat st;
+
+ if (fstat (fileno (stream), &st) >= 0 && S_ISREG (st.st_mode))
+ {
+ off_t pos = ftello (stream);
+
+ if (pos >= 0 && pos < st.st_size)
+ {
+ off_t alloc_off = st.st_size - pos;
+
+ /* '1' below, accounts for the trailing NUL. */
+ if (PTRDIFF_MAX - 1 < alloc_off)
+ {
+ errno = ENOMEM;
+ return NULL;
+ }
+
+ alloc = alloc_off + 1;
+ }
+ }
+ }
+
+ if (!(buf = malloc (alloc)))
+ return NULL; /* errno is ENOMEM. */
+
+ {
+ size_t size = 0; /* number of bytes read so far */
+ int save_errno;
+
+ for (;;)
+ {
+ /* This reads 1 more than the size of a regular file
+ so that we get eof immediately. */
+ size_t requested = alloc - size;
+ size_t count = fread (buf + size, 1, requested, stream);
+ size += count;
+
+ if (count != requested)
+ {
+ save_errno = errno;
+ if (ferror (stream))
+ break;
+
+ /* Shrink the allocated memory if possible. */
+ if (size < alloc - 1)
+ {
+ if (flags & RF_SENSITIVE)
+ {
+ char *smaller_buf = malloc (size + 1);
+ if (smaller_buf == NULL)
+ explicit_bzero (buf + size, alloc - size);
+ else
+ {
+ memcpy (smaller_buf, buf, size);
+ explicit_bzero (buf, alloc);
+ free (buf);
+ buf = smaller_buf;
+ }
+ }
+ else
+ {
+ char *smaller_buf = realloc (buf, size + 1);
+ if (smaller_buf != NULL)
+ buf = smaller_buf;
+ }
+ }
+
+ buf[size] = '\0';
+ *length = size;
+ return buf;
+ }
+
+ {
+ char *new_buf;
+ size_t save_alloc = alloc;
+
+ if (alloc == PTRDIFF_MAX)
+ {
+ save_errno = ENOMEM;
+ break;
+ }
+
+ if (alloc < PTRDIFF_MAX - alloc / 2)
+ alloc = alloc + alloc / 2;
+ else
+ alloc = PTRDIFF_MAX;
+
+ if (flags & RF_SENSITIVE)
+ {
+ new_buf = malloc (alloc);
+ if (!new_buf)
+ {
+ /* BUF should be cleared below after the loop. */
+ save_errno = errno;
+ break;
+ }
+ memcpy (new_buf, buf, save_alloc);
+ explicit_bzero (buf, save_alloc);
+ free (buf);
+ }
+ else if (!(new_buf = realloc (buf, alloc)))
+ {
+ save_errno = errno;
+ break;
+ }
+
+ buf = new_buf;
+ }
+ }
+
+ if (flags & RF_SENSITIVE)
+ explicit_bzero (buf, alloc);
+
+ free (buf);
+ errno = save_errno;
+ return NULL;
+ }
+}
+
+/* Open and read the contents of FILENAME, and return a newly
+ allocated string with the content, and set *LENGTH to the length of
+ the string. The string is zero-terminated, but the terminating
+ zero byte is not counted in *LENGTH. On errors, *LENGTH is
+ undefined, errno preserves the values set by system functions (if
+ any), and NULL is returned.
+
+ If the RF_BINARY flag is set in FLAGS, the file is opened in binary
+ mode. If the RF_SENSITIVE flag is set in FLAGS, the memory buffer
+ internally allocated will be cleared upon failure. */
+char *
+read_file (const char *filename, int flags, size_t *length)
+{
+ const char *mode = (flags & RF_BINARY) ? "rbe" : "re";
+ FILE *stream = fopen (filename, mode);
+ char *out;
+
+ if (!stream)
+ return NULL;
+
+ if (flags & RF_SENSITIVE)
+ setvbuf (stream, NULL, _IONBF, 0);
+
+ out = fread_file (stream, flags, length);
+
+ if (fclose (stream) != 0)
+ {
+ if (out)
+ {
+ if (flags & RF_SENSITIVE)
+ explicit_bzero (out, *length);
+ free (out);
+ }
+ return NULL;
+ }
+
+ return out;
+}