linuxdebug/tools/perf/util/demangle-ocaml.c

69 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <string.h>
#include <stdlib.h>
#include "util/string2.h"
#include "demangle-ocaml.h"
#include <linux/ctype.h>
static const char *caml_prefix = "caml";
static const size_t caml_prefix_len = 4;
/* mangled OCaml symbols start with "caml" followed by an upper-case letter */
static bool
ocaml_is_mangled(const char *sym)
{
return 0 == strncmp(sym, caml_prefix, caml_prefix_len)
&& isupper(sym[caml_prefix_len]);
}
/*
* input:
* sym: a symbol which may have been mangled by the OCaml compiler
* return:
* if the input doesn't look like a mangled OCaml symbol, NULL is returned
* otherwise, a newly allocated string containing the demangled symbol is returned
*/
char *
ocaml_demangle_sym(const char *sym)
{
char *result;
int j = 0;
int i;
int len;
if (!ocaml_is_mangled(sym)) {
return NULL;
}
len = strlen(sym);
/* the demangled symbol is always smaller than the mangled symbol */
result = malloc(len + 1);
if (!result)
return NULL;
/* skip "caml" prefix */
i = caml_prefix_len;
while (i < len) {
if (sym[i] == '_' && sym[i + 1] == '_') {
/* "__" -> "." */
result[j++] = '.';
i += 2;
}
else if (sym[i] == '$' && isxdigit(sym[i + 1]) && isxdigit(sym[i + 2])) {
/* "$xx" is a hex-encoded character */
result[j++] = (hex(sym[i + 1]) << 4) | hex(sym[i + 2]);
i += 3;
}
else {
result[j++] = sym[i++];
}
}
result[j] = '\0';
return result;
}