summaryrefslogtreecommitdiff
path: root/util/libreboot-utils/lib/string.c
diff options
context:
space:
mode:
Diffstat (limited to 'util/libreboot-utils/lib/string.c')
-rw-r--r--util/libreboot-utils/lib/string.c643
1 files changed, 0 insertions, 643 deletions
diff --git a/util/libreboot-utils/lib/string.c b/util/libreboot-utils/lib/string.c
deleted file mode 100644
index 7388cf35..00000000
--- a/util/libreboot-utils/lib/string.c
+++ /dev/null
@@ -1,643 +0,0 @@
-/* SPDX-License-Identifier: MIT
- * Copyright (c) 2026 Leah Rowe <leah@libreboot.org>
- *
- * String functions
- */
-
-#include <sys/types.h>
-#include <sys/stat.h>
-
-#include <errno.h>
-#include <stdarg.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <limits.h>
-#include <stdint.h>
-
-#include "../include/common.h"
-
-/* for null detection inside
- * word-optimised string functions
- */
-#define ff ((size_t)-1 / 0xFF)
-#define high ((ff) * 0x80)
-/* NOTE:
- * do not assume that a match means
- * both words have null at the same
- * location. see how this is handled
- * e.g. in scmp.
- */
-#define zeroes(x) (((x) - (ff)) & ~(x) & (high))
-
-size_t
-page_remain(const void *p)
-{
- /* calling sysconf repeatedly
- * is folly. cache it (static)
- */
- static size_t pagesz = 0;
- if (!pagesz)
- pagesz = (size_t)pagesize();
-
- return pagesz - ((uintptr_t)p & (pagesz - 1));
-}
-
-long
-pagesize(void)
-{
- static long rval = 0;
- static int set = 0;
- int saved_errno = 0;
-
- if (!set) {
- if ((rval = sysconf(_SC_PAGESIZE)) < 0)
- exitf("could not determine page size");
- set = 1;
- }
-
- reset_caller_errno(0);
- return rval;
-}
-
-void
-free_and_set_null(char **buf)
-{
- if (buf == NULL)
- exitf(
- "null ptr (to ptr for freeing) in free_and_set_null");
-
- if (*buf == NULL)
- return;
-
- free(*buf);
- *buf = NULL;
-}
-
-/* safe(ish) malloc.
-
- use this and free_and_set_null()
- in your program, to reduce the
- chance of use after frees!
-
- if you use these functions in the
- intended way, you will greatly reduce
- the number of bugs in your code
- */
-char *
-smalloc(char **buf, size_t size)
-{
- return (char *)vmalloc((void **)buf, size);
-}
-void *
-vmalloc(void **buf, size_t size)
-{
- int saved_errno = errno;
- void *rval = NULL;
- errno = 0;
-
- if (size >= SIZE_MAX - 1)
- exitf("integer overflow in vmalloc");
- if (buf == NULL)
- exitf("Bad pointer passed to vmalloc");
-
- /* lots of programs will
- * re-initialise a buffer
- * that was allocated, without
- * freeing or NULLing it. this
- * is here intentionally, to
- * force the programmer to behave
- */
- if (*buf != NULL)
- exitf("Non-null pointer given to vmalloc");
-
- if (!size)
- exitf(
- "Tried to vmalloc(0) and that is very bad. Fix it now");
-
- if ((rval = malloc(size)) == NULL)
- exitf("malloc fail in vmalloc");
-
- reset_caller_errno(0);
- return *buf = rval;
-}
-
-/* strict word-based strcmp */
-int
-scmp(const char *a,
- const char *b,
- size_t maxlen,
- int *rval)
-{
- size_t i = 0;
- size_t j;
- size_t wa;
- size_t wb;
- int saved_errno = errno;
- errno = 0;
-
- if (if_err(a == NULL || b == NULL || rval == NULL, EFAULT))
- goto err;
-
- for ( ; ((uintptr_t)(a + i) % sizeof(size_t)) != 0; i++) {
-
- if (if_err(i >= maxlen, EOVERFLOW))
- goto err;
- else if (!ccmp(a, b, i, rval))
- goto out;
- }
-
- for ( ; i + sizeof(size_t) <= maxlen;
- i += sizeof(size_t)) {
-
- /* prevent crossing page boundary on word check */
- if (page_remain(a + i) < sizeof(size_t) ||
- page_remain(b + i) < sizeof(size_t))
- break;
-
- memcpy(&wa, a + i, sizeof(size_t));
- memcpy(&wb, b + i, sizeof(size_t));
-
- if (wa != wb)
- for (j = 0; j < sizeof(size_t); j++)
- if (!ccmp(a, b, i + j, rval))
- goto out;
-
- if (!zeroes(wa))
- continue;
-
- *rval = 0;
- goto out;
- }
-
- for ( ; i < maxlen; i++)
- if (!ccmp(a, b, i, rval))
- goto out;
-
-err:
- (void) with_fallback_errno(EFAULT);
- if (rval != NULL)
- *rval = -1;
-
- exitf("scmp");
- return -1;
-out:
- reset_caller_errno(0);
- return *rval;
-}
-
-int ccmp(const char *a, const char *b,
- size_t i, int *rval)
-{
- unsigned char ac;
- unsigned char bc;
-
- if (if_err(a == NULL || b == NULL || rval == NULL, EFAULT))
- exitf("ccmp");
-
- ac = (unsigned char)a[i];
- bc = (unsigned char)b[i];
-
- if (ac != bc) {
- *rval = ac - bc;
- return 0;
- } else if (ac == '\0') {
- *rval = 0;
- return 0;
- }
-
- return 1;
-}
-
-/* strict word-based strlen */
-size_t
-slen(const char *s,
- size_t maxlen,
- size_t *rval)
-{
- int saved_errno = errno;
- size_t i = 0;
- size_t w;
- size_t j;
- errno = 0;
-
- if (if_err(s == NULL || rval == NULL, EFAULT))
- goto err;
-
- for ( ; ((uintptr_t)(s + i) % sizeof(size_t)) != 0; i++) {
-
- if (if_err(i >= maxlen, EOVERFLOW))
- goto err;
- if (s[i] == '\0') {
- *rval = i;
- goto out;
- }
- }
-
- for ( ; i + sizeof(size_t) <= maxlen;
- i += sizeof(size_t)) {
-
- memcpy(&w, s + i, sizeof(size_t));
- if (!zeroes(w))
- continue;
-
- for (j = 0; j < sizeof(size_t); j++) {
- if (s[i + j] == '\0') {
- *rval = i + j;
- goto out;
- }
- }
- }
-
- for ( ; i < maxlen; i++) {
- if (s[i] == '\0') {
- *rval = i;
- goto out;
- }
- }
-
-err:
- (void) with_fallback_errno(EFAULT);
- if (rval != NULL)
- *rval = 0;
-
- exitf("slen"); /* abort */
- return 0; /* gcc15 is happy */
-out:
- reset_caller_errno(0);
- return *rval;
-}
-
-int
-dup_pair(char **dir, const char *d,
- char **base, const char *b)
-{
- char *dtmp = NULL;
- char *btmp = NULL;
-
- if (d && sdup(d, PATH_MAX, &dtmp) == NULL)
- return -1;
-
- if (b && sdup(b, PATH_MAX, &btmp) == NULL) {
- free(dtmp);
- return -1;
- }
-
- *dir = dtmp;
- *base = btmp;
-
- return 0;
-}
-
-/* strict word-based strdup */
-char *
-sdup(const char *s,
- size_t max, char **dest)
-{
- size_t j;
- size_t w;
- size_t i = 0;
- char *out = NULL;
- int saved_errno = errno;
- errno = 0;
-
- if (if_err(dest == NULL || *dest != NULL || s == NULL, EFAULT))
- goto err;
-
- out = smalloc(dest, max);
-
- for ( ; ((uintptr_t)(s + i) % sizeof(size_t)) != 0; i++) {
-
- if (if_err(i >= max, EOVERFLOW))
- goto err;
-
- out[i] = s[i];
- if (s[i] == '\0') {
- *dest = out;
- goto out;
- }
- }
-
- for ( ; i + sizeof(size_t) <= max; i += sizeof(size_t)) {
-
- if (page_remain(s + i) < sizeof(size_t))
- break;
-
- memcpy(&w, s + i, sizeof(size_t));
- if (!zeroes(w)) {
- memcpy(out + i, &w, sizeof(size_t));
- continue;
- }
-
- for (j = 0; j < sizeof(size_t); j++) {
-
- out[i + j] = s[i + j];
- if (s[i + j] == '\0') {
- *dest = out;
- goto out;
- }
- }
- }
-
- for ( ; i < max; i++) {
-
- out[i] = s[i];
- if (s[i] == '\0') {
- *dest = out;
- goto out;
- }
- }
-
-err:
- free_and_set_null(&out);
- if (dest != NULL)
- *dest = NULL;
-
- (void) with_fallback_errno(EFAULT);
- exitf("sdup");
-
- return NULL;
-out:
- reset_caller_errno(0);
- return *dest;
-}
-
-/* concatenate N number of strings */
-char *
-scatn(ssize_t sc, const char **sv,
- size_t max, char **rval)
-{
- int saved_errno = errno;
- char *final = NULL;
- char *rcur = NULL;
- char *rtmp = NULL;
- ssize_t i;
- errno = 0;
-
- if (if_err(sc < 2, EINVAL) ||
- if_err(sv == NULL, EFAULT) ||
- if_err(rval == NULL || *rval != NULL, EFAULT))
- goto err;
-
- for (i = 0; i < sc; i++) {
-
- if (if_err(sv[i] == NULL, EFAULT))
- goto err;
- else if (i == 0) {
- (void) sdup(sv[0], max, &final);
- continue;
- }
-
- rtmp = NULL;
- scat(final, sv[i], max, &rtmp);
-
- free_and_set_null(&final);
- final = rtmp;
- rtmp = NULL;
- }
-
- reset_caller_errno(0);
- *rval = final;
- return *rval;
-err:
- free_and_set_null(&rcur);
- free_and_set_null(&rtmp);
- free_and_set_null(&final);
-
- (void) with_fallback_errno(EFAULT);
-
- exitf("scatn");
- return NULL;
-}
-
-/* strict strcat */
-char *
-scat(const char *s1, const char *s2,
- size_t n, char **dest)
-{
- size_t size1;
- size_t size2;
- char *rval = NULL;
- int saved_errno = errno;
- errno = 0;
-
- if (if_err(dest == NULL || *dest != NULL, EFAULT))
- goto err;
-
- slen(s1, n, &size1);
- slen(s2, n, &size2);
-
- if (if_err(size1
- > SIZE_MAX - size2 - 1, EOVERFLOW))
- goto err;
-
- smalloc(&rval, size1 + size2 + 1);
-
- memcpy(rval, s1, size1);
- memcpy(rval + size1, s2, size2);
- *(rval + size1 + size2) = '\0';
-
- reset_caller_errno(0);
- *dest = rval;
- return *dest;
-err:
- (void) with_fallback_errno(EINVAL);
- if (dest != NULL)
- *dest = NULL;
- exitf("scat");
-
- return NULL;
-}
-
-/* strict split/de-cat - off is where
- 2nd buffer will start from */
-void
-dcat(const char *s, size_t n,
- size_t off, char **dest1,
- char **dest2)
-{
- size_t size;
- char *rval1 = NULL;
- char *rval2 = NULL;
- int saved_errno = errno;
- errno = 0;
-
- if (if_err(dest1 == NULL || dest2 == NULL, EFAULT))
- goto err;
-
- if (if_err(slen(s, n, &size) >= SIZE_MAX - 1, EOVERFLOW) ||
- if_err(off >= size, EOVERFLOW))
- goto err;
-
- memcpy(smalloc(&rval1, off + 1),
- s, off);
- *(rval1 + off) = '\0';
-
- memcpy(smalloc(&rval2, size - off +1),
- s + off, size - off);
- *(rval2 + size - off) = '\0';
-
- *dest1 = rval1;
- *dest2 = rval2;
-
- reset_caller_errno(0);
- return;
-
-err:
- *dest1 = *dest2 = NULL;
-
- free_and_set_null(&rval1);
- free_and_set_null(&rval2);
-
- (void) with_fallback_errno(EINVAL);
- exitf("dcat");
-}
-
-/* because no libc reimagination is complete
- * without a reimplementation of memcmp. and
- * no safe one is complete without null checks.
- */
-int
-vcmp(const void *s1, const void *s2, size_t n)
-{
- int saved_errno = errno;
- size_t i = 0;
- size_t a;
- size_t b;
-
- const unsigned char *x;
- const unsigned char *y;
- errno = 0;
-
- if (if_err(s1 == NULL || s2 == NULL, EFAULT))
- exitf("vcmp: null input");
-
- x = s1;
- y = s2;
-
- for ( ; i + sizeof(size_t) <= n; i += sizeof(size_t)) {
-
- memcpy(&a, x + i, sizeof(size_t));
- memcpy(&b, y + i, sizeof(size_t));
-
- if (a != b)
- break;
- }
-
- for ( ; i < n; i++)
- if (x[i] != y[i])
- return (int)x[i] - (int)y[i];
-
- reset_caller_errno(0);
- return 0;
-}
-
-/* on functions that return with errno,
- * i sometimes have a default fallback,
- * which is set if errno wasn't changed,
- * under error condition.
- */
-int
-with_fallback_errno(int fallback)
-{
- if (!errno)
- errno = fallback;
- return -1;
-}
-
-/* the one for nvmutil state is in state.c */
-/* this one just exits */
-void
-exitf(const char *msg, ...)
-{
- va_list args;
- int saved_errno = errno;
-
- func_t err_cleanup = errhook(NULL);
- err_cleanup();
- reset_caller_errno(0);
- saved_errno = errno;
-
- if (!errno)
- saved_errno = errno = ECANCELED;
-
- fprintf(stderr, "%s: ", lbgetprogname());
-
- va_start(args, msg);
- vfprintf(stderr, msg, args);
- va_end(args);
-
- errno = saved_errno;
- fprintf(stderr, ": %s\n", strerror(errno));
-
- exit(EXIT_FAILURE);
-}
-
-/* the err function will
- * call this upon exit, and
- * cleanup will be performed
- * e.g. you might want to
- * close some files, depending
- * on your program.
- * see: exitf()
- */
-func_t errhook(func_t ptr)
-{
- static int set = 0;
- static func_t hook = NULL;
-
- if (!set) {
- set = 1;
-
- if (ptr == NULL)
- hook = no_op;
- else
- hook = ptr;
- }
-
- return hook;
-}
-
-void
-no_op(void)
-{
- return;
-}
-
-const char *
-lbgetprogname(void)
-{
- char *name = lbsetprogname(NULL);
- char *p = NULL;
- if (name)
- p = strrchr(name, '/');
- if (p)
- return p + 1;
- else if (name)
- return name;
- else
- return "libreboot-utils";
-}
-
-/* singleton. if string not null,
- sets the string. after set,
- will not set anymore. either
- way, returns the string
- */
-char *
-lbsetprogname(char *argv0)
-{
- static char *progname = NULL;
- static int set = 0;
-
- if (!set) {
- if (argv0 == NULL)
- return "libreboot-utils";
- (void) sdup(argv0, PATH_MAX, &progname);
- set = 1;
- }
-
- return progname;
-}
generated by cgit v1.2.1 (git 2.18.0) at 2026-09-22 10:00:58 +0000