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scripts/kallsyms: add sym_name() to mitigate cast ugliness

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sym_entry::sym is (unsigned char *) instead of (char *) because
kallsyms exploits the MSB for compression, and the characters are
used as the index of token_profit array.

However, it requires casting (unsigned char *) to (char *) in some
places since standard library functions such as strcmp(), strlen()
expect (char *).

Introduce a new helper, sym_name(), which advances the given pointer
by 1 and casts it to (char *).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This commit is contained in:
Masahiro Yamada 2019-11-24 01:04:35 +09:00
parent c5e5002f36
commit 29e55ad3d5
1 changed files with 16 additions and 13 deletions
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29
scripts/kallsyms.c
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@ -74,6 +74,11 @@ static void usage(void)
exit(1);
}
static char *sym_name(const struct sym_entry *s)
{
return (char *)s->sym + 1;
}
static int check_symbol_range(const char *sym, unsigned long long addr,
struct addr_range *ranges, int entries)
{
@ -154,7 +159,7 @@ static int read_symbol(FILE *in, struct sym_entry *s)
"unable to allocate required amount of memory\n");
exit(EXIT_FAILURE);
}
strcpy((char *)s->sym + 1, sym);
strcpy(sym_name(s), sym);
s->sym[0] = stype;
s->percpu_absolute = 0;
@ -215,7 +220,7 @@ static int symbol_valid(struct sym_entry *s)
NULL };
int i;
char *sym_name = (char *)s->sym + 1;
const char *name = sym_name(s);
/* if --all-symbols is not specified, then symbols outside the text
* and inittext sections are discarded */
@ -230,30 +235,28 @@ static int symbol_valid(struct sym_entry *s)
* rules.
*/
if ((s->addr == text_range_text->end &&
strcmp(sym_name,
text_range_text->end_sym)) ||
strcmp(name, text_range_text->end_sym)) ||
(s->addr == text_range_inittext->end &&
strcmp(sym_name,
text_range_inittext->end_sym)))
strcmp(name, text_range_inittext->end_sym)))
return 0;
}
/* Exclude symbols which vary between passes. */
for (i = 0; special_symbols[i]; i++)
if (strcmp(sym_name, special_symbols[i]) == 0)
if (strcmp(name, special_symbols[i]) == 0)
return 0;
for (i = 0; special_prefixes[i]; i++) {
int l = strlen(special_prefixes[i]);
if (strncmp(sym_name, special_prefixes[i], l) == 0)
if (strncmp(name, special_prefixes[i], l) == 0)
return 0;
}
for (i = 0; special_suffixes[i]; i++) {
int l = strlen(sym_name) - strlen(special_suffixes[i]);
int l = strlen(name) - strlen(special_suffixes[i]);
if (l >= 0 && strcmp(sym_name + l, special_suffixes[i]) == 0)
if (l >= 0 && strcmp(name + l, special_suffixes[i]) == 0)
return 0;
}
@ -626,7 +629,7 @@ static void optimize_token_table(void)
/* guess for "linker script provide" symbol */
static int may_be_linker_script_provide_symbol(const struct sym_entry *se)
{
const char *symbol = (char *)se->sym + 1;
const char *symbol = sym_name(se);
int len = se->len - 1;
if (len < 8)
@ -696,8 +699,8 @@ static int compare_symbols(const void *a, const void *b)
return wa - wb;
/* sort by the number of prefix underscores */
wa = prefix_underscores_count((const char *)sa->sym + 1);
wb = prefix_underscores_count((const char *)sb->sym + 1);
wa = prefix_underscores_count(sym_name(sa));
wb = prefix_underscores_count(sym_name(sb));
if (wa != wb)
return wa - wb;