[PATCH 07/29] modpost: use read_text_file() and get_line() for reading text files

Masahiro Yamada
2020-05-17T09:50:24Z

grab_file() mmaps a file, but it is not so efficient here because
get_next_line() copies every line to the temporary buffer anyway.

read_text_file() and get_line() are simpler. get_line() exploits the
library function strchr().

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

scripts/mod/modpost.c | 15 ++++++++-------
scripts/mod/sumversion.c | 11 ++++++-----
2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 2c6319f0ce19..8021f7e93448 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -2466,15 +2466,16 @@ static void write_if_changed(struct buffer *b, const char *fname)
**/
static void read_dump(const char *fname, unsigned int kernel)
{
- unsigned long size, pos = 0;
- void *file = grab_file(fname, &size);
- char *line;
+ char *buf, *pos, *line;

- if (!file)
+ buf = read_text_file(fname);
+ if (!buf)
/* No symbol versions, silently ignore */
return;

- while ((line = get_next_line(&pos, file, size))) {
+ pos = buf;
+
+ while ((line = get_line(&pos))) {
char *symname, *namespace, *modname, *d, *export;
unsigned int crc;
struct module *mod;
@@ -2509,10 +2510,10 @@ static void read_dump(const char *fname, unsigned int kernel)
sym_set_crc(symname, crc);
sym_update_namespace(symname, namespace);
}
- release_file(file, size);
+ free(buf);
return;
fail:
- release_file(file, size);
+ free(buf);
fatal("parse error in symbol dump file\n");
}

diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c
index a1c7b0f4cd5a..89c8baefde9d 100644
--- a/scripts/mod/sumversion.c
+++ b/scripts/mod/sumversion.c
@@ -306,9 +306,8 @@ static int is_static_library(const char *objfile)
* to figure out source files. */
static int parse_source_files(const char *objfile, struct md4_ctx *md)
{
- char *cmd, *file, *line, *dir;
+ char *cmd, *file, *line, *dir, *pos;
const char *base;
- unsigned long flen, pos = 0;
int dirlen, ret = 0, check_files = 0;

cmd = NOFAIL(malloc(strlen(objfile) + sizeof("..cmd")));
@@ -326,14 +325,16 @@ static int parse_source_files(const char *objfile, struct md4_ctx *md)
strncpy(dir, objfile, dirlen);
dir[dirlen] = '\0';

- file = grab_file(cmd, &flen);
+ file = read_text_file(cmd);
if (!file) {
warn("could not find %s for %s\n", cmd, objfile);
goto out;
}

+ pos = file;
+
/* Sum all files in the same dir or subdirs. */
- while ((line = get_next_line(&pos, file, flen)) != NULL) {
+ while ((line = get_line(&pos))) {
char* p = line;

if (strncmp(line, "source_", sizeof("source_")-1) == 0) {
@@ -384,7 +385,7 @@ static int parse_source_files(const char *objfile, struct md4_ctx *md)
/* Everyone parsed OK */
ret = 1;
out_file:
- release_file(file, flen);
+ free(file);
out:
free(dir);
free(cmd);
--
2.25.1