view kconfig/util.c @ 1613:96aa7ec74936 draft

Fix yet another sed bug. The s/// command would copy the \ of substitutions before deciding what to do with them (generally overwriting the \ with the new data). When the substitution was A) at the very end of the new string, B) resolved to nothing, it could leave a trailing \ that didn't belong there and didn't get overwritten because the "copy trailing data" part that copies the original string's null terminator already happened before the \ overwrote it. The ghostwheel() function restarts regexes after embedded NUL bytes, but if the string it's passed is _longer_ than the length it's told then it gets confused (and it means we're off the end of our allocation so segfaults are likely). Fix: test for \ first and move the "copy byte" logic into an else case.
author Rob Landley <>
date Mon, 15 Dec 2014 03:34:55 -0600
parents 4d21d59f3206
line wrap: on
line source

 * Copyright (C) 2002-2005 Roman Zippel <>
 * Copyright (C) 2002-2005 Sam Ravnborg <>
 * Released under the terms of the GNU GPL v2.0.

#include <string.h>
#include "lkc.h"

/* file already present in list? If not add it */
struct file *file_lookup(const char *name)
	struct file *file;

	for (file = file_list; file; file = file->next) {
		if (!strcmp(name, file->name))
			return file;

	file = malloc(sizeof(*file));
	memset(file, 0, sizeof(*file));
	file->name = strdup(name);
	file->next = file_list;
	file_list = file;
	return file;

/* write a dependency file as used by kbuild to track dependencies */
int file_write_dep(const char *name)
	struct file *file;
	FILE *out;

	if (!name)
		name = ".kconfig.d";
	out = fopen("..config.tmp", "w");
	if (!out)
		return 1;
	fprintf(out, "deps_config := \\\n");
	for (file = file_list; file; file = file->next) {
		if (file->next)
			fprintf(out, "\t%s \\\n", file->name);
			fprintf(out, "\t%s\n", file->name);
	fprintf(out, "\ninclude/config/auto.conf: \\\n"
		     "$(deps_config): ;\n");
	rename("..config.tmp", name);
	return 0;

/* Allocate initial growable sting */
struct gstr str_new(void)
	struct gstr gs;
	gs.s = malloc(sizeof(char) * 64);
	gs.len = 16;
	strcpy(gs.s, "\0");
	return gs;

/* Allocate and assign growable string */
struct gstr str_assign(const char *s)
	struct gstr gs;
	gs.s = strdup(s);
	gs.len = strlen(s) + 1;
	return gs;

/* Free storage for growable string */
void str_free(struct gstr *gs)
	if (gs->s)
	gs->s = NULL;
	gs->len = 0;

/* Append to growable string */
void str_append(struct gstr *gs, const char *s)
	size_t l = strlen(gs->s) + strlen(s) + 1;
	if (l > gs->len) {
		gs->s   = realloc(gs->s, l);
		gs->len = l;
	strcat(gs->s, s);

/* Append printf formatted string to growable string */
void str_printf(struct gstr *gs, const char *fmt, ...)
	va_list ap;
	char s[10000]; /* big enough... */
	va_start(ap, fmt);
	vsnprintf(s, sizeof(s), fmt, ap);
	str_append(gs, s);

/* Retrieve value of growable string */
const char *str_get(struct gstr *gs)
	return gs->s;