kexec-tools/SOURCES/kexec-tools-2.0.20-03-add_slurp_proc_file_.patch
2022-05-07 10:10:42 +00:00

77 lines
1.8 KiB
Diff

commit 193e51deccc62544f6423eb5e5eefc8a23aad679
Author: Sven Schnelle <svens@linux.ibm.com>
Date: Thu Dec 16 12:43:54 2021 +0100
add slurp_proc_file()
slurp_file() cannot be used to read proc files, as they are returning
a size of zero in stat(). Add a function slurp_proc_file() which is
similar to slurp_file(), but doesn't require the size of the file to
be known.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
diff --git a/kexec/kexec.c b/kexec/kexec.c
index f63b36b771eb95a93f07a7c286c4974a558aec8d..f3adac517161d448552a16fd79488c1df100d356 100644
--- a/kexec/kexec.c
+++ b/kexec/kexec.c
@@ -1106,6 +1106,57 @@ static void remove_parameter(char *line, const char *param_name)
}
}
+static ssize_t _read(int fd, void *buf, size_t count)
+{
+ ssize_t ret, offset = 0;
+
+ do {
+ ret = read(fd, buf + offset, count - offset);
+ if (ret < 0) {
+ if ((errno == EINTR) || (errno == EAGAIN))
+ continue;
+ return ret;
+ }
+ offset += ret;
+ } while (ret && offset < count);
+
+ return offset;
+}
+
+static char *slurp_proc_file(const char *filename, size_t *len)
+{
+ ssize_t ret, startpos = 0;
+ unsigned int size = 64;
+ char *buf = NULL, *tmp;
+ int fd;
+
+ fd = open(filename, O_RDONLY);
+ if (fd == -1)
+ return NULL;
+
+ do {
+ size *= 2;
+ tmp = realloc(buf, size);
+ if (!tmp) {
+ free(buf);
+ return NULL;
+ }
+ buf = tmp;
+
+ ret = _read(fd, buf + startpos, size - startpos);
+ if (ret < 0) {
+ free(buf);
+ return NULL;
+ }
+
+ startpos += ret;
+
+ } while(ret);
+
+ *len = startpos;
+ return buf;
+}
+
/*
* Returns the contents of the current command line to be used with
* --reuse-cmdline option. The function gets called from architecture specific