[PATCH 2/4] modpost: use strstarts() helper more widely

From: Masahiro Yamada
Date: Wed May 09 2018 - 05:51:36 EST


Currently, strstarts() is only used in export_from_secname().
Use it more widely to improve the code readability.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

scripts/mod/modpost.c | 39 ++++++++++++++++++---------------------
1 file changed, 18 insertions(+), 21 deletions(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 37a6a0b4..8606b6c 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -596,19 +596,19 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname)
return 1;
if (info->hdr->e_machine == EM_PPC)
/* Special register function linked on all modules during final link of .ko */
- if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
- strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
- strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
- strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0 ||
- strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
- strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0)
+ if (strstarts(symname, "_restgpr_") ||
+ strstarts(symname, "_savegpr_") ||
+ strstarts(symname, "_rest32gpr_") ||
+ strstarts(symname, "_save32gpr_") ||
+ strstarts(symname, "_restvr_") ||
+ strstarts(symname, "_savevr_"))
return 1;
if (info->hdr->e_machine == EM_PPC64)
/* Special register function linked on all modules during final link of .ko */
- if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
- strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0 ||
- strncmp(symname, "_restvr_", sizeof("_restvr_") - 1) == 0 ||
- strncmp(symname, "_savevr_", sizeof("_savevr_") - 1) == 0 ||
+ if (strstarts(symname, "_restgpr0_") ||
+ strstarts(symname, "_savegpr0_") ||
+ strstarts(symname, "_restvr_") ||
+ strstarts(symname, "_savevr_") ||
strcmp(symname, ".TOC.") == 0)
return 1;
/* Do not ignore this symbol */
@@ -623,13 +623,13 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
bool is_crc = false;

if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
- strncmp(symname, "__ksymtab", 9) == 0)
+ strstarts(symname, "__ksymtab"))
export = export_from_secname(info, get_secindex(info, sym));
else
export = export_from_sec(info, get_secindex(info, sym));

/* CRC'd symbol */
- if (strncmp(symname, "__crc_", strlen("__crc_")) == 0) {
+ if (strstarts(symname, "__crc_")) {
is_crc = true;
crc = (unsigned int) sym->st_value;
if (sym->st_shndx != SHN_UNDEF && sym->st_shndx != SHN_ABS) {
@@ -648,7 +648,7 @@ static void handle_modversions(struct module *mod, struct elf_info *info,

switch (sym->st_shndx) {
case SHN_COMMON:
- if (!strncmp(symname, "__gnu_lto_", sizeof("__gnu_lto_")-1)) {
+ if (strstarts(symname, "__gnu_lto_")) {
/* Should warn here, but modpost runs before the linker */
} else
warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
@@ -691,7 +691,7 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
break;
default:
/* All exported symbols */
- if (strncmp(symname, "__ksymtab_", strlen("__ksymtab_")) == 0) {
+ if (strstarts(symname, "__ksymtab_")) {
sym_add_exported(symname + strlen("__ksymtab_"), mod,
export);
}
@@ -1171,13 +1171,13 @@ static int secref_whitelist(const struct sectioncheck *mismatch,
/* Check for pattern 1 */
if (match(tosec, init_data_sections) &&
match(fromsec, data_sections) &&
- (strncmp(fromsym, "__param", strlen("__param")) == 0))
+ strstarts(fromsym, "__param"))
return 0;

/* Check for pattern 1a */
if (strcmp(tosec, ".init.text") == 0 &&
match(fromsec, data_sections) &&
- (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0))
+ strstarts(fromsym, "__param_ops_"))
return 0;

/* Check for pattern 2 */
@@ -1532,8 +1532,7 @@ static void default_mismatch_handler(const char *modname, struct elf_info *elf,
from = find_elf_symbol2(elf, r->r_offset, fromsec);
fromsym = sym_name(elf, from);

- if (!strncmp(fromsym, "reference___initcall",
- sizeof("reference___initcall")-1))
+ if (strstarts(fromsym, "reference___initcall"))
return;

tosec = sec_name(elf, get_secindex(elf, sym));
@@ -2163,9 +2162,7 @@ static void add_retpoline(struct buffer *b)

static void add_staging_flag(struct buffer *b, const char *name)
{
- static const char *staging_dir = "drivers/staging";
-
- if (strncmp(staging_dir, name, strlen(staging_dir)) == 0)
+ if (strstarts(name, "drivers/staging"))
buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
}

--
2.7.4