https://github.com/torvalds/linux
Tip revision: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476 authored by Linus Torvalds on 11 December 2022, 22:15:18 UTC
Linux 6.1
Linux 6.1
Tip revision: 830b3c6
util.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2011 The Chromium Authors, All Rights Reserved.
* Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
*
* util_is_printable_string contributed by
* Pantelis Antoniou <pantelis.antoniou AT gmail.com>
*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include <inttypes.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include "libfdt.h"
#include "util.h"
#include "version_gen.h"
char *xstrdup(const char *s)
{
int len = strlen(s) + 1;
char *d = xmalloc(len);
memcpy(d, s, len);
return d;
}
int xavsprintf_append(char **strp, const char *fmt, va_list ap)
{
int n, size = 0; /* start with 128 bytes */
char *p;
va_list ap_copy;
p = *strp;
if (p)
size = strlen(p);
va_copy(ap_copy, ap);
n = vsnprintf(NULL, 0, fmt, ap_copy) + 1;
va_end(ap_copy);
p = xrealloc(p, size + n);
n = vsnprintf(p + size, n, fmt, ap);
*strp = p;
return strlen(p);
}
int xasprintf_append(char **strp, const char *fmt, ...)
{
int n;
va_list ap;
va_start(ap, fmt);
n = xavsprintf_append(strp, fmt, ap);
va_end(ap);
return n;
}
int xasprintf(char **strp, const char *fmt, ...)
{
int n;
va_list ap;
*strp = NULL;
va_start(ap, fmt);
n = xavsprintf_append(strp, fmt, ap);
va_end(ap);
return n;
}
char *join_path(const char *path, const char *name)
{
int lenp = strlen(path);
int lenn = strlen(name);
int len;
int needslash = 1;
char *str;
len = lenp + lenn + 2;
if ((lenp > 0) && (path[lenp-1] == '/')) {
needslash = 0;
len--;
}
str = xmalloc(len);
memcpy(str, path, lenp);
if (needslash) {
str[lenp] = '/';
lenp++;
}
memcpy(str+lenp, name, lenn+1);
return str;
}
bool util_is_printable_string(const void *data, int len)
{
const char *s = data;
const char *ss, *se;
/* zero length is not */
if (len == 0)
return 0;
/* must terminate with zero */
if (s[len - 1] != '\0')
return 0;
se = s + len;
while (s < se) {
ss = s;
while (s < se && *s && isprint((unsigned char)*s))
s++;
/* not zero, or not done yet */
if (*s != '\0' || s == ss)
return 0;
s++;
}
return 1;
}
/*
* Parse a octal encoded character starting at index i in string s. The
* resulting character will be returned and the index i will be updated to
* point at the character directly after the end of the encoding, this may be
* the '\0' terminator of the string.
*/
static char get_oct_char(const char *s, int *i)
{
char x[4];
char *endx;
long val;
x[3] = '\0';
strncpy(x, s + *i, 3);
val = strtol(x, &endx, 8);
assert(endx > x);
(*i) += endx - x;
return val;
}
/*
* Parse a hexadecimal encoded character starting at index i in string s. The
* resulting character will be returned and the index i will be updated to
* point at the character directly after the end of the encoding, this may be
* the '\0' terminator of the string.
*/
static char get_hex_char(const char *s, int *i)
{
char x[3];
char *endx;
long val;
x[2] = '\0';
strncpy(x, s + *i, 2);
val = strtol(x, &endx, 16);
if (!(endx > x))
die("\\x used with no following hex digits\n");
(*i) += endx - x;
return val;
}
char get_escape_char(const char *s, int *i)
{
char c = s[*i];
int j = *i + 1;
char val;
switch (c) {
case 'a':
val = '\a';
break;
case 'b':
val = '\b';
break;
case 't':
val = '\t';
break;
case 'n':
val = '\n';
break;
case 'v':
val = '\v';
break;
case 'f':
val = '\f';
break;
case 'r':
val = '\r';
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
j--; /* need to re-read the first digit as
* part of the octal value */
val = get_oct_char(s, &j);
break;
case 'x':
val = get_hex_char(s, &j);
break;
default:
val = c;
}
(*i) = j;
return val;
}
int utilfdt_read_err(const char *filename, char **buffp, size_t *len)
{
int fd = 0; /* assume stdin */
char *buf = NULL;
size_t bufsize = 1024, offset = 0;
int ret = 0;
*buffp = NULL;
if (strcmp(filename, "-") != 0) {
fd = open(filename, O_RDONLY);
if (fd < 0)
return errno;
}
/* Loop until we have read everything */
buf = xmalloc(bufsize);
do {
/* Expand the buffer to hold the next chunk */
if (offset == bufsize) {
bufsize *= 2;
buf = xrealloc(buf, bufsize);
}
ret = read(fd, &buf[offset], bufsize - offset);
if (ret < 0) {
ret = errno;
break;
}
offset += ret;
} while (ret != 0);
/* Clean up, including closing stdin; return errno on error */
close(fd);
if (ret)
free(buf);
else
*buffp = buf;
if (len)
*len = bufsize;
return ret;
}
char *utilfdt_read(const char *filename, size_t *len)
{
char *buff;
int ret = utilfdt_read_err(filename, &buff, len);
if (ret) {
fprintf(stderr, "Couldn't open blob from '%s': %s\n", filename,
strerror(ret));
return NULL;
}
/* Successful read */
return buff;
}
int utilfdt_write_err(const char *filename, const void *blob)
{
int fd = 1; /* assume stdout */
int totalsize;
int offset;
int ret = 0;
const char *ptr = blob;
if (strcmp(filename, "-") != 0) {
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
if (fd < 0)
return errno;
}
totalsize = fdt_totalsize(blob);
offset = 0;
while (offset < totalsize) {
ret = write(fd, ptr + offset, totalsize - offset);
if (ret < 0) {
ret = -errno;
break;
}
offset += ret;
}
/* Close the file/stdin; return errno on error */
if (fd != 1)
close(fd);
return ret < 0 ? -ret : 0;
}
int utilfdt_write(const char *filename, const void *blob)
{
int ret = utilfdt_write_err(filename, blob);
if (ret) {
fprintf(stderr, "Couldn't write blob to '%s': %s\n", filename,
strerror(ret));
}
return ret ? -1 : 0;
}
int utilfdt_decode_type(const char *fmt, int *type, int *size)
{
int qualifier = 0;
if (!*fmt)
return -1;
/* get the conversion qualifier */
*size = -1;
if (strchr("hlLb", *fmt)) {
qualifier = *fmt++;
if (qualifier == *fmt) {
switch (*fmt++) {
/* TODO: case 'l': qualifier = 'L'; break;*/
case 'h':
qualifier = 'b';
break;
}
}
}
/* we should now have a type */
if ((*fmt == '\0') || !strchr("iuxs", *fmt))
return -1;
/* convert qualifier (bhL) to byte size */
if (*fmt != 's')
*size = qualifier == 'b' ? 1 :
qualifier == 'h' ? 2 :
qualifier == 'l' ? 4 : -1;
*type = *fmt++;
/* that should be it! */
if (*fmt)
return -1;
return 0;
}
void utilfdt_print_data(const char *data, int len)
{
int i;
const char *s;
/* no data, don't print */
if (len == 0)
return;
if (util_is_printable_string(data, len)) {
printf(" = ");
s = data;
do {
printf("\"%s\"", s);
s += strlen(s) + 1;
if (s < data + len)
printf(", ");
} while (s < data + len);
} else if ((len % 4) == 0) {
const fdt32_t *cell = (const fdt32_t *)data;
printf(" = <");
for (i = 0, len /= 4; i < len; i++)
printf("0x%08" PRIx32 "%s", fdt32_to_cpu(cell[i]),
i < (len - 1) ? " " : "");
printf(">");
} else {
const unsigned char *p = (const unsigned char *)data;
printf(" = [");
for (i = 0; i < len; i++)
printf("%02x%s", *p++, i < len - 1 ? " " : "");
printf("]");
}
}
void NORETURN util_version(void)
{
printf("Version: %s\n", DTC_VERSION);
exit(0);
}
void NORETURN util_usage(const char *errmsg, const char *synopsis,
const char *short_opts,
struct option const long_opts[],
const char * const opts_help[])
{
FILE *fp = errmsg ? stderr : stdout;
const char a_arg[] = "<arg>";
size_t a_arg_len = strlen(a_arg) + 1;
size_t i;
int optlen;
fprintf(fp,
"Usage: %s\n"
"\n"
"Options: -[%s]\n", synopsis, short_opts);
/* prescan the --long opt length to auto-align */
optlen = 0;
for (i = 0; long_opts[i].name; ++i) {
/* +1 is for space between --opt and help text */
int l = strlen(long_opts[i].name) + 1;
if (long_opts[i].has_arg == a_argument)
l += a_arg_len;
if (optlen < l)
optlen = l;
}
for (i = 0; long_opts[i].name; ++i) {
/* helps when adding new applets or options */
assert(opts_help[i] != NULL);
/* first output the short flag if it has one */
if (long_opts[i].val > '~')
fprintf(fp, " ");
else
fprintf(fp, " -%c, ", long_opts[i].val);
/* then the long flag */
if (long_opts[i].has_arg == no_argument)
fprintf(fp, "--%-*s", optlen, long_opts[i].name);
else
fprintf(fp, "--%s %s%*s", long_opts[i].name, a_arg,
(int)(optlen - strlen(long_opts[i].name) - a_arg_len), "");
/* finally the help text */
fprintf(fp, "%s\n", opts_help[i]);
}
if (errmsg) {
fprintf(fp, "\nError: %s\n", errmsg);
exit(EXIT_FAILURE);
} else
exit(EXIT_SUCCESS);
}