X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fuci.git;a=blobdiff_plain;f=file.c;h=63ca9193725a46f0fee4ce4d17305dcf48ca50c9;hp=8e7f0ce82b2a2e6790bb0e8c762833df00953f3a;hb=ecf0ed555ebc1b8e5b6aba54bb06a907bb4aecf2;hpb=4b1ddfb8358bcd57560406db26d7041c9c0cb90b

diff --git a/file.c b/file.c
index 8e7f0ce..63ca919 100644
--- a/file.c
+++ b/file.c
@@ -2,44 +2,43 @@
  * libuci - Library for the Unified Configuration Interface
  * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
  *
- * this program is free software; you can redistribute it and/or modify
- * it under the terms of the gnu lesser general public license version 2.1
- * as published by the free software foundation
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
+ * GNU Lesser General Public License for more details.
  */
 
 /*
  * This file contains the code for parsing uci config files
  */
 
+#define _GNU_SOURCE
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/file.h>
 #include <stdbool.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <ctype.h>
+#include <glob.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "uci.h"
+#include "uci_internal.h"
 
 #define LINEBUF	32
 #define LINEBUF_MAX	4096
 
-static void uci_parse_error(struct uci_context *ctx, char *pos, char *reason)
-{
-	struct uci_parse_context *pctx = ctx->pctx;
-
-	pctx->reason = reason;
-	pctx->byte = pos - pctx->buf;
-	UCI_THROW(ctx, UCI_ERR_PARSE);
-}
-
 /*
  * Fetch a new line from the input stream and resize buffer if necessary
  */
-static void uci_getln(struct uci_context *ctx, int offset)
+__private void uci_getln(struct uci_context *ctx, int offset)
 {
 	struct uci_parse_context *pctx = ctx->pctx;
 	char *p;
@@ -49,11 +48,16 @@ static void uci_getln(struct uci_context *ctx, int offset)
 		pctx->buf = uci_malloc(ctx, LINEBUF);
 		pctx->bufsz = LINEBUF;
 	}
+	/* `offset' may off by one */
+	if (offset >= pctx->bufsz) {
+		pctx->bufsz *= 2;
+		pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
+	}
 
 	ofs = offset;
 	do {
 		p = &pctx->buf[ofs];
-		p[ofs] = 0;
+		p[0] = 0;
 
 		p = fgets(p, pctx->bufsz - ofs, pctx->file);
 		if (!p || !*p)
@@ -62,12 +66,11 @@ static void uci_getln(struct uci_context *ctx, int offset)
 		ofs += strlen(p);
 		if (pctx->buf[ofs - 1] == '\n') {
 			pctx->line++;
-			pctx->buf[ofs - 1] = 0;
 			return;
 		}
 
 		if (pctx->bufsz > LINEBUF_MAX/2)
-			uci_parse_error(ctx, p, "line too long");
+			uci_parse_error(ctx, "line too long");
 
 		pctx->bufsz *= 2;
 		pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
@@ -75,46 +78,24 @@ static void uci_getln(struct uci_context *ctx, int offset)
 }
 
 /*
- * Clean up all extra memory used by the parser and exporter
- */
-static void uci_file_cleanup(struct uci_context *ctx)
-{
-	struct uci_parse_context *pctx;
-
-	if (ctx->buf) {
-		free(ctx->buf);
-		ctx->buf = NULL;
-		ctx->bufsz = 0;
-	}
-
-	pctx = ctx->pctx;
-	if (!pctx)
-		return;
-
-	ctx->pctx = NULL;
-	if (pctx->package)
-		uci_free_package(&pctx->package);
-
-	if (pctx->buf)
-		free(pctx->buf);
-
-	free(pctx);
-}
-
-/* 
  * parse a character escaped by '\'
  * returns true if the escaped character is to be parsed
  * returns false if the escaped character is to be ignored
  */
-static inline bool parse_backslash(struct uci_context *ctx, char **str)
+static bool parse_backslash(struct uci_context *ctx)
 {
+	struct uci_parse_context *pctx = ctx->pctx;
+
 	/* skip backslash */
-	*str += 1;
+	pctx->pos += 1;
 
 	/* undecoded backslash at the end of line, fetch the next line */
-	if (!**str) {
-		*str += 1;
-		uci_getln(ctx, *str - ctx->pctx->buf);
+	if (!pctx_cur_char(pctx) ||
+	    pctx_cur_char(pctx) == '\n' ||
+	    (pctx_cur_char(pctx) == '\r' &&
+	     pctx_char(pctx, pctx_pos(pctx) + 1) == '\n' &&
+	     !pctx_char(pctx, pctx_pos(pctx) + 2))) {
+		uci_getln(ctx, pctx->pos);
 		return false;
 	}
 
@@ -126,151 +107,242 @@ static inline bool parse_backslash(struct uci_context *ctx, char **str)
  * move the string pointer forward until a non-whitespace character or
  * EOL is reached
  */
-static void skip_whitespace(struct uci_context *ctx, char **str)
+static void skip_whitespace(struct uci_context *ctx)
 {
-restart:
-	while (**str && isspace(**str))
-		*str += 1;
+	struct uci_parse_context *pctx = ctx->pctx;
 
-	if (**str == '\\') {
-		if (!parse_backslash(ctx, str))
-			goto restart;
-	}
+	while (pctx_cur_char(pctx) && isspace(pctx_cur_char(pctx)))
+		pctx->pos += 1;
 }
 
-static inline void addc(char **dest, char **src)
+static inline void addc(struct uci_context *ctx, int *pos_dest, int *pos_src)
 {
-	**dest = **src;
-	*dest += 1;
-	*src += 1;
+	struct uci_parse_context *pctx = ctx->pctx;
+
+	pctx_char(pctx, *pos_dest) = pctx_char(pctx, *pos_src);
+	*pos_dest += 1;
+	*pos_src += 1;
 }
 
 /*
  * parse a double quoted string argument from the command line
  */
-static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
+static void parse_double_quote(struct uci_context *ctx, int *target)
 {
+	struct uci_parse_context *pctx = ctx->pctx;
 	char c;
 
 	/* skip quote character */
-	*str += 1;
+	pctx->pos += 1;
 
-	while ((c = **str)) {
+	while (1) {
+		c = pctx_cur_char(pctx);
 		switch(c) {
 		case '"':
-			**target = 0;
-			*str += 1;
+			pctx->pos += 1;
 			return;
+		case 0:
+			/* Multi-line str value */
+			uci_getln(ctx, pctx->pos);
+			if (!pctx_cur_char(pctx)) {
+				uci_parse_error(ctx, "EOF with unterminated \"");
+			}
+			break;
 		case '\\':
-			if (!parse_backslash(ctx, str))
+			if (!parse_backslash(ctx))
 				continue;
 			/* fall through */
 		default:
-			addc(target, str);
+			addc(ctx, target, &pctx->pos);
 			break;
 		}
 	}
-	uci_parse_error(ctx, *str, "unterminated \"");
+	uci_parse_error(ctx, "unterminated \"");
 }
 
 /*
  * parse a single quoted string argument from the command line
  */
-static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
+static void parse_single_quote(struct uci_context *ctx, int *target)
 {
+	struct uci_parse_context *pctx = ctx->pctx;
 	char c;
 	/* skip quote character */
-	*str += 1;
+	pctx->pos += 1;
 
-	while ((c = **str)) {
+	while (1) {
+		c = pctx_cur_char(pctx);
 		switch(c) {
 		case '\'':
-			**target = 0;
-			*str += 1;
+			pctx->pos += 1;
 			return;
+		case 0:
+			/* Multi-line str value */
+			uci_getln(ctx, pctx->pos);
+			if (!pctx_cur_char(pctx))
+				uci_parse_error(ctx, "EOF with unterminated \"");
+
+			break;
 		default:
-			addc(target, str);
+			addc(ctx, target, &pctx->pos);
 		}
 	}
-	uci_parse_error(ctx, *str, "unterminated '");
+	uci_parse_error(ctx, "unterminated '");
 }
 
 /*
  * parse a string from the command line and detect the quoting style
  */
-static void parse_str(struct uci_context *ctx, char **str, char **target)
+static void parse_str(struct uci_context *ctx, int *target)
 {
+	struct uci_parse_context *pctx = ctx->pctx;
+	bool next = true;
 	do {
-		switch(**str) {
+		switch(pctx_cur_char(pctx)) {
 		case '\'':
-			parse_single_quote(ctx, str, target);
+			parse_single_quote(ctx, target);
 			break;
 		case '"':
-			parse_double_quote(ctx, str, target);
+			parse_double_quote(ctx, target);
 			break;
+		case '#':
+			pctx_cur_char(pctx) = 0;
+			/* fall through */
 		case 0:
 			goto done;
+		case ';':
+			next = false;
+			goto done;
 		case '\\':
-			if (!parse_backslash(ctx, str))
+			if (!parse_backslash(ctx))
 				continue;
 			/* fall through */
 		default:
-			addc(target, str);
+			addc(ctx, target, &pctx->pos);
 			break;
 		}
-	} while (**str && !isspace(**str));
+	} while (pctx_cur_char(pctx) && !isspace(pctx_cur_char(pctx)));
 done:
 
-	/* 
+	/*
 	 * if the string was unquoted and we've stopped at a whitespace
 	 * character, skip to the next one, because the whitespace will
 	 * be overwritten by a null byte here
 	 */
-	if (**str)
-		*str += 1;
+	if (pctx_cur_char(pctx) && next)
+		pctx->pos += 1;
 
 	/* terminate the parsed string */
-	**target = 0;
+	pctx_char(pctx, *target) = 0;
 }
 
 /*
  * extract the next argument from the command line
  */
-static char *next_arg(struct uci_context *ctx, char **str, bool required, bool name)
+static char *next_arg(struct uci_context *ctx, bool required, bool name)
 {
-	char *val;
-	char *ptr;
-
-	val = ptr = *str;
-	skip_whitespace(ctx, str);
-	parse_str(ctx, str, &ptr);
-	if (!*val) {
+	struct uci_parse_context *pctx = ctx->pctx;
+	int val, ptr;
+
+	skip_whitespace(ctx);
+	val = ptr = pctx_pos(pctx);
+	if (pctx_cur_char(pctx) == ';') {
+		pctx_cur_char(pctx) = 0;
+		pctx->pos += 1;
+	} else {
+		parse_str(ctx, &ptr);
+	}
+	if (!pctx_char(pctx, val)) {
 		if (required)
-			uci_parse_error(ctx, *str, "insufficient arguments");
+			uci_parse_error(ctx, "insufficient arguments");
 		goto done;
 	}
 
-	if (name && !uci_validate_name(val))
-		uci_parse_error(ctx, val, "invalid character in field");
+	if (name && !uci_validate_name(pctx_str(pctx, val)))
+		uci_parse_error(ctx, "invalid character in name field");
 
 done:
-	return val;
+	return pctx_str(pctx, val);
+}
+
+int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
+{
+	UCI_HANDLE_ERR(ctx);
+	UCI_ASSERT(ctx, str != NULL);
+	UCI_ASSERT(ctx, result != NULL);
+
+	if (ctx->pctx && (ctx->pctx->file != stream))
+		uci_cleanup(ctx);
+
+	if (!ctx->pctx)
+		uci_alloc_parse_context(ctx);
+
+	ctx->pctx->file = stream;
+
+	if (!*str) {
+		uci_getln(ctx, 0);
+		*str = ctx->pctx->buf;
+	} else {
+		UCI_ASSERT(ctx, ctx->pctx->pos == *str - ctx->pctx->buf);
+	}
+
+	*result = next_arg(ctx, false, false);
+
+	return 0;
+}
+
+static int
+uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
+{
+	UCI_ASSERT(ctx, ptr != NULL);
+	UCI_ASSERT(ctx, e != NULL);
+
+	memset(ptr, 0, sizeof(struct uci_ptr));
+	switch(e->type) {
+	case UCI_TYPE_OPTION:
+		ptr->o = uci_to_option(e);
+		goto fill_option;
+	case UCI_TYPE_SECTION:
+		ptr->s = uci_to_section(e);
+		goto fill_section;
+	case UCI_TYPE_PACKAGE:
+		ptr->p = uci_to_package(e);
+		goto fill_package;
+	default:
+		UCI_THROW(ctx, UCI_ERR_INVAL);
+	}
+
+fill_option:
+	ptr->option = ptr->o->e.name;
+	ptr->s = ptr->o->section;
+fill_section:
+	ptr->section = ptr->s->e.name;
+	ptr->p = ptr->s->package;
+fill_package:
+	ptr->package = ptr->p->e.name;
+
+	ptr->flags |= UCI_LOOKUP_DONE;
+
+	return 0;
 }
 
+
+
 /*
  * verify that the end of the line or command is reached.
  * throw an error if extra arguments are given on the command line
  */
-static void assert_eol(struct uci_context *ctx, char **str)
+static void assert_eol(struct uci_context *ctx)
 {
 	char *tmp;
 
-	tmp = next_arg(ctx, str, false, false);
-	if (tmp && *tmp)
-		uci_parse_error(ctx, *str, "too many arguments");
+	skip_whitespace(ctx);
+	tmp = next_arg(ctx, false, false);
+	if (*tmp && (ctx->flags & UCI_FLAG_STRICT))
+		uci_parse_error(ctx, "too many arguments");
 }
 
-/* 
+/*
  * switch to a different config, either triggered by uci_load, or by a
  * 'package <...>' statement in the import file
  */
@@ -285,6 +357,7 @@ static void uci_switch_config(struct uci_context *ctx)
 
 	/* add the last config to main config file list */
 	if (pctx->package) {
+		pctx->package->backend = ctx->backend;
 		uci_list_add(&ctx->root, &pctx->package->e.list);
 
 		pctx->package = NULL;
@@ -294,11 +367,11 @@ static void uci_switch_config(struct uci_context *ctx)
 	if (!name)
 		return;
 
-	/* 
+	/*
 	 * if an older config under the same name exists, unload it
 	 * ignore errors here, e.g. if the config was not found
 	 */
-	e = uci_lookup_list(ctx, &ctx->root, name);
+	e = uci_lookup_list(&ctx->root, name);
 	if (e)
 		UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 	pctx->package = uci_alloc_package(ctx, name);
@@ -307,15 +380,16 @@ static void uci_switch_config(struct uci_context *ctx)
 /*
  * parse the 'package' uci command (next config package)
  */
-static void uci_parse_package(struct uci_context *ctx, char **str, bool single)
+static void uci_parse_package(struct uci_context *ctx, bool single)
 {
+	struct uci_parse_context *pctx = ctx->pctx;
 	char *name = NULL;
 
 	/* command string null-terminated by strtok */
-	*str += strlen(*str) + 1;
+	pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 
-	name = next_arg(ctx, str, true, true);
-	assert_eol(ctx, str);
+	name = next_arg(ctx, true, true);
+	assert_eol(ctx);
 	if (single)
 		return;
 
@@ -323,116 +397,85 @@ static void uci_parse_package(struct uci_context *ctx, char **str, bool single)
 	uci_switch_config(ctx);
 }
 
-/* Based on an efficient hash function published by D. J. Bernstein */
-static unsigned int djbhash(unsigned int hash, char *str)
-{
-	int len = strlen(str);
-	int i;
-
-	/* initial value */
-	if (hash == ~0)
-		hash = 5381;
-
-	for(i = 0; i < len; i++) {
-		hash = ((hash << 5) + hash) + str[i];
-	}
-	return (hash & 0x7FFFFFFF);
-}
-
-/* fix up an unnamed section */
-static void uci_fixup_section(struct uci_context *ctx, struct uci_section *s)
-{
-	unsigned int hash = ~0;
-	struct uci_element *e;
-	char buf[16];
-
-	if (!s || s->e.name)
-		return;
-
-	/*
-	 * Generate a name for unnamed sections. This is used as reference
-	 * when locating or updating the section from apps/scripts.
-	 * To make multiple concurrent versions somewhat safe for updating,
-	 * the name is generated from a hash of its type and name/value
-	 * pairs of its option, and it is prefixed by a counter value.
-	 * If the order of the unnamed sections changes for some reason,
-	 * updates to them will be rejected.
-	 */
-	hash = djbhash(hash, s->type);
-	uci_foreach_element(&s->options, e) {
-		hash = djbhash(hash, e->name);
-		hash = djbhash(hash, uci_to_option(e)->value);
-	}
-	sprintf(buf, "cfg%02x%04x", ++s->package->n_section, hash % (1 << 16));
-	s->e.name = uci_strdup(ctx, buf);
-}
-
 /*
  * parse the 'config' uci command (open a section)
  */
-static void uci_parse_config(struct uci_context *ctx, char **str)
+static void uci_parse_config(struct uci_context *ctx)
 {
 	struct uci_parse_context *pctx = ctx->pctx;
-	struct uci_section *s;
+	struct uci_element *e;
+	struct uci_ptr ptr;
 	char *name = NULL;
 	char *type = NULL;
 
 	uci_fixup_section(ctx, ctx->pctx->section);
 	if (!ctx->pctx->package) {
 		if (!ctx->pctx->name)
-			uci_parse_error(ctx, *str, "attempting to import a file without a package name");
+			uci_parse_error(ctx, "attempting to import a file without a package name");
 
 		uci_switch_config(ctx);
 	}
 
 	/* command string null-terminated by strtok */
-	*str += strlen(*str) + 1;
-
-	type = next_arg(ctx, str, true, true);
-	name = next_arg(ctx, str, false, true);
-	assert_eol(ctx, str);
-
-	if (pctx->merge) {
-		UCI_TRAP_SAVE(ctx, error);
-		uci_set(ctx, pctx->package, name, NULL, type);
-		UCI_TRAP_RESTORE(ctx);
-		return;
-error:
-		UCI_THROW(ctx, ctx->errno);
-	} else
-		pctx->section = uci_alloc_section(pctx->package, type, name);
+	pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
+
+	type = next_arg(ctx, true, false);
+	if (!uci_validate_type(type))
+		uci_parse_error(ctx, "invalid character in type field");
+	name = next_arg(ctx, false, true);
+	assert_eol(ctx);
+
+	if (!name || !name[0]) {
+		ctx->internal = !pctx->merge;
+		UCI_NESTED(uci_add_section, ctx, pctx->package, type, &pctx->section);
+	} else {
+		uci_fill_ptr(ctx, &ptr, &pctx->package->e);
+		e = uci_lookup_list(&pctx->package->sections, name);
+		if (e)
+			ptr.s = uci_to_section(e);
+		ptr.section = name;
+		ptr.value = type;
+
+		ctx->internal = !pctx->merge;
+		UCI_NESTED(uci_set, ctx, &ptr);
+		pctx->section = uci_to_section(ptr.last);
+	}
 }
 
 /*
  * parse the 'option' uci command (open a value)
  */
-static void uci_parse_option(struct uci_context *ctx, char **str)
+static void uci_parse_option(struct uci_context *ctx, bool list)
 {
 	struct uci_parse_context *pctx = ctx->pctx;
+	struct uci_element *e;
+	struct uci_ptr ptr;
 	char *name = NULL;
 	char *value = NULL;
 
 	if (!pctx->section)
-		uci_parse_error(ctx, *str, "option command found before the first section");
+		uci_parse_error(ctx, "option/list command found before the first section");
 
 	/* command string null-terminated by strtok */
-	*str += strlen(*str) + 1;
+	pctx->pos += strlen(pctx_cur_str(pctx)) + 1;
 
-	name = next_arg(ctx, str, true, true);
-	value = next_arg(ctx, str, true, false);
-	assert_eol(ctx, str);
+	name = next_arg(ctx, true, true);
+	value = next_arg(ctx, false, false);
+	assert_eol(ctx);
 
-	if (pctx->merge) {
-		UCI_TRAP_SAVE(ctx, error);
-		uci_set(ctx, pctx->package, pctx->section->e.name, name, value);
-		UCI_TRAP_RESTORE(ctx);
-		return;
-error:
-		UCI_THROW(ctx, ctx->errno);
-	} else
-		uci_alloc_option(pctx->section, name, value);
-}
+	uci_fill_ptr(ctx, &ptr, &pctx->section->e);
+	e = uci_lookup_list(&pctx->section->options, name);
+	if (e)
+		ptr.o = uci_to_option(e);
+	ptr.option = name;
+	ptr.value = value;
 
+	ctx->internal = !pctx->merge;
+	if (list)
+		UCI_NESTED(uci_add_list, ctx, &ptr);
+	else
+		UCI_NESTED(uci_set, ctx, &ptr);
+}
 
 /*
  * parse a complete input line, split up combined commands by ';'
@@ -440,33 +483,50 @@ error:
 static void uci_parse_line(struct uci_context *ctx, bool single)
 {
 	struct uci_parse_context *pctx = ctx->pctx;
-	char *word, *brk = NULL;
+	char *word;
 
-	for (word = strtok_r(pctx->buf, ";", &brk);
-		 word;
-		 word = strtok_r(NULL, ";", &brk)) {
-
-		char *pbrk = NULL;
-		word = strtok_r(word, " \t", &pbrk);
+	/* Skip whitespace characters at the start of line */
+	skip_whitespace(ctx);
+	do {
+		word = strtok(pctx_cur_str(pctx), " \t");
+		if (!word)
+			return;
 
 		switch(word[0]) {
+			case 0:
+			case '#':
+				return;
 			case 'p':
 				if ((word[1] == 0) || !strcmp(word + 1, "ackage"))
-					uci_parse_package(ctx, &word, single);
+					uci_parse_package(ctx, single);
+				else
+					goto invalid;
 				break;
 			case 'c':
 				if ((word[1] == 0) || !strcmp(word + 1, "onfig"))
-					uci_parse_config(ctx, &word);
+					uci_parse_config(ctx);
+				else
+					goto invalid;
 				break;
 			case 'o':
 				if ((word[1] == 0) || !strcmp(word + 1, "ption"))
-					uci_parse_option(ctx, &word);
+					uci_parse_option(ctx, false);
+				else
+					goto invalid;
 				break;
-			default:
-				uci_parse_error(ctx, word, "unterminated command");
+			case 'l':
+				if ((word[1] == 0) || !strcmp(word + 1, "ist"))
+					uci_parse_option(ctx, true);
+				else
+					goto invalid;
 				break;
+			default:
+				goto invalid;
 		}
-	}
+		continue;
+invalid:
+		uci_parse_error(ctx, "invalid command");
+	} while (1);
 }
 
 /* max number of characters that escaping adds to the string */
@@ -475,62 +535,83 @@ static void uci_parse_line(struct uci_context *ctx, bool single)
 /*
  * escape an uci string for export
  */
-static char *uci_escape(struct uci_context *ctx, char *str)
+static const char *uci_escape(struct uci_context *ctx, const char *str)
 {
-	char *s, *p;
-	int pos = 0;
+	const char *end;
+	int ofs = 0;
 
 	if (!ctx->buf) {
 		ctx->bufsz = LINEBUF;
 		ctx->buf = malloc(LINEBUF);
+
+		if (!ctx->buf)
+			return str;
 	}
 
-	s = str;
-	p = strchr(str, '\'');
-	if (!p)
-		return str;
+	while (1) {
+		int len;
 
-	do {
-		int len = p - s;
-		if (len > 0) {
-			if (p + sizeof(UCI_QUOTE_ESCAPE) - str >= ctx->bufsz) {
-				ctx->bufsz *= 2;
-				ctx->buf = realloc(ctx->buf, ctx->bufsz);
-				if (!ctx->buf)
-					UCI_THROW(ctx, UCI_ERR_MEM);
-			}
-			memcpy(&ctx->buf[pos], s, len);
-			pos += len;
+		end = strchr(str, '\'');
+		if (!end)
+			end = str + strlen(str);
+		len = end - str;
+
+		/* make sure that we have enough room in the buffer */
+		while (ofs + len + sizeof(UCI_QUOTE_ESCAPE) + 1 > ctx->bufsz) {
+			ctx->bufsz *= 2;
+			ctx->buf = uci_realloc(ctx, ctx->buf, ctx->bufsz);
 		}
-		strcpy(&ctx->buf[pos], UCI_QUOTE_ESCAPE);
-		pos += sizeof(UCI_QUOTE_ESCAPE);
-		s = p + 1;
-	} while ((p = strchr(s, '\'')));
 
+		/* copy the string until the character before the quote */
+		memcpy(&ctx->buf[ofs], str, len);
+		ofs += len;
+
+		/* end of string? return the buffer */
+		if (*end == 0)
+			break;
+
+		memcpy(&ctx->buf[ofs], UCI_QUOTE_ESCAPE, sizeof(UCI_QUOTE_ESCAPE));
+		ofs += strlen(&ctx->buf[ofs]);
+		str = end + 1;
+	}
+
+	ctx->buf[ofs] = 0;
 	return ctx->buf;
 }
 
-
 /*
  * export a single config package to a file stream
  */
 static void uci_export_package(struct uci_package *p, FILE *stream, bool header)
 {
 	struct uci_context *ctx = p->ctx;
-	struct uci_element *s, *o;
+	struct uci_element *s, *o, *i;
 
 	if (header)
-		fprintf(stream, "package '%s'\n", uci_escape(ctx, p->e.name));
+		fprintf(stream, "package %s\n", uci_escape(ctx, p->e.name));
 	uci_foreach_element(&p->sections, s) {
 		struct uci_section *sec = uci_to_section(s);
-		fprintf(stream, "\nconfig '%s'", uci_escape(ctx, sec->type));
-		if (!sec->anonymous)
+		fprintf(stream, "\nconfig %s", uci_escape(ctx, sec->type));
+		if (!sec->anonymous || (ctx->flags & UCI_FLAG_EXPORT_NAME))
 			fprintf(stream, " '%s'", uci_escape(ctx, sec->e.name));
 		fprintf(stream, "\n");
 		uci_foreach_element(&sec->options, o) {
 			struct uci_option *opt = uci_to_option(o);
-			fprintf(stream, "\toption '%s'", uci_escape(ctx, opt->e.name));
-			fprintf(stream, " '%s'\n", uci_escape(ctx, opt->value));
+			switch(opt->type) {
+			case UCI_TYPE_STRING:
+				fprintf(stream, "\toption %s", uci_escape(ctx, opt->e.name));
+				fprintf(stream, " '%s'\n", uci_escape(ctx, opt->v.string));
+				break;
+			case UCI_TYPE_LIST:
+				uci_foreach_element(&opt->v.list, i) {
+					fprintf(stream, "\tlist %s", uci_escape(ctx, opt->e.name));
+					fprintf(stream, " '%s'\n", uci_escape(ctx, i->name));
+				}
+				break;
+			default:
+				fprintf(stream, "\t# unknown type for option '%s'\n", uci_escape(ctx, opt->e.name));
+				break;
+			}
 		}
 	}
 	fprintf(stream, "\n");
@@ -560,12 +641,12 @@ int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct u
 	UCI_HANDLE_ERR(ctx);
 
 	/* make sure no memory from previous parse attempts is leaked */
-	uci_file_cleanup(ctx);
+	uci_cleanup(ctx);
 
-	pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
-	ctx->pctx = pctx;
+	uci_alloc_parse_context(ctx);
+	pctx = ctx->pctx;
 	pctx->file = stream;
-	if (*package && single) {
+	if (package && *package && single) {
 		pctx->package = *package;
 		pctx->merge = true;
 	}
@@ -575,10 +656,13 @@ int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct u
 	 * the appropriate 'package <name>' string to specify the config name
 	 * NB: the config file can still override the package name
 	 */
-	if (name)
+	if (name) {
+		UCI_ASSERT(ctx, uci_validate_package(name));
 		pctx->name = name;
+	}
 
 	while (!feof(pctx->file)) {
+		pctx->pos = 0;
 		uci_getln(ctx, 0);
 		UCI_TRAP_SAVE(ctx, error);
 		if (pctx->buf[0])
@@ -588,12 +672,14 @@ int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct u
 error:
 		if (ctx->flags & UCI_FLAG_PERROR)
 			uci_perror(ctx, NULL);
-		if ((ctx->errno != UCI_ERR_PARSE) ||
+		if ((ctx->err != UCI_ERR_PARSE) ||
 			(ctx->flags & UCI_FLAG_STRICT))
-			UCI_THROW(ctx, ctx->errno);
+			UCI_THROW(ctx, ctx->err);
 	}
 
 	uci_fixup_section(ctx, ctx->pctx->section);
+	if (!pctx->package && name)
+		uci_switch_config(ctx);
 	if (package)
 		*package = pctx->package;
 	if (pctx->merge)
@@ -603,291 +689,33 @@ error:
 	uci_switch_config(ctx);
 
 	/* no error happened, we can get rid of the parser context now */
-	uci_file_cleanup(ctx);
+	uci_cleanup(ctx);
 
 	return 0;
 }
 
-/*
- * open a stream and go to the right position
- *
- * note: when opening for write and seeking to the beginning of
- * the stream, truncate the file
- */
-static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int pos, bool write, bool create)
-{
-	struct stat statbuf;
-	FILE *file = NULL;
-	int fd, ret;
-	int mode = (write ? O_RDWR : O_RDONLY);
-
-	if (create)
-		mode |= O_CREAT;
-
-	if (!write && ((stat(filename, &statbuf) < 0) ||
-		((statbuf.st_mode &  S_IFMT) != S_IFREG))) {
-		UCI_THROW(ctx, UCI_ERR_NOTFOUND);
-	}
-
-	fd = open(filename, mode, UCI_FILEMODE);
-	if (fd <= 0)
-		goto error;
-
-	if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)
-		goto error;
-
-	ret = lseek(fd, 0, pos);
-
-	if (ret < 0)
-		goto error;
-
-	file = fdopen(fd, (write ? "w+" : "r"));
-	if (file)
-		goto done;
-
-error:
-	UCI_THROW(ctx, UCI_ERR_IO);
-done:
-	return file;
-}
-
-static void uci_close_stream(FILE *stream)
-{
-	int fd;
-
-	if (!stream)
-		return;
-
-	fd = fileno(stream);
-	flock(fd, LOCK_UN);
-	fclose(stream);
-}
-
-static void uci_parse_history_line(struct uci_context *ctx, struct uci_package *p, char *buf)
-{
-	bool delete = false;
-	bool rename = false;
-	char *package = NULL;
-	char *section = NULL;
-	char *option = NULL;
-	char *value = NULL;
-
-	if (buf[0] == '-') {
-		delete = true;
-		buf++;
-	} else if (buf[0] == '@') {
-		rename = true;
-		buf++;
-	}
-
-	UCI_INTERNAL(uci_parse_tuple, ctx, buf, &package, &section, &option, &value);
-	if (!package || !section || (!delete && !value))
-		goto error;
-	if (strcmp(package, p->e.name) != 0)
-		goto error;
-	if (!uci_validate_name(section))
-		goto error;
-	if (option && !uci_validate_name(option))
-		goto error;
-
-	if (rename)
-		UCI_INTERNAL(uci_rename, ctx, p, section, option, value);
-	else if (delete)
-		UCI_INTERNAL(uci_delete, ctx, p, section, option);
-	else
-		UCI_INTERNAL(uci_set, ctx, p, section, option, value);
-
-	return;
-error:
-	UCI_THROW(ctx, UCI_ERR_PARSE);
-}
-
-static void uci_parse_history(struct uci_context *ctx, FILE *stream, struct uci_package *p)
-{
-	struct uci_parse_context *pctx;
-
-	/* make sure no memory from previous parse attempts is leaked */
-	uci_file_cleanup(ctx);
-
-	pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
-	ctx->pctx = pctx;
-	pctx->file = stream;
-
-	while (!feof(pctx->file)) {
-		uci_getln(ctx, 0);
-		if (!pctx->buf[0])
-			continue;
-
-		/*
-		 * ignore parse errors in single lines, we want to preserve as much
-		 * history as possible
-		 */
-		UCI_TRAP_SAVE(ctx, error);
-		uci_parse_history_line(ctx, p, pctx->buf);
-		UCI_TRAP_RESTORE(ctx);
-error:
-		continue;
-	}
-
-	/* no error happened, we can get rid of the parser context now */
-	uci_file_cleanup(ctx);
-}
-
-static void uci_load_history(struct uci_context *ctx, struct uci_package *p, bool flush)
-{
-	char *filename = NULL;
-	FILE *f = NULL;
-
-	if (!p->confdir)
-		return;
-	if ((asprintf(&filename, "%s/%s", UCI_SAVEDIR, p->e.name) < 0) || !filename)
-		UCI_THROW(ctx, UCI_ERR_MEM);
-
-	UCI_TRAP_SAVE(ctx, done);
-	f = uci_open_stream(ctx, filename, SEEK_SET, flush, false);
-	if (p)
-		uci_parse_history(ctx, f, p);
-	UCI_TRAP_RESTORE(ctx);
-
-done:
-	if (flush && f) {
-		rewind(f);
-		ftruncate(fileno(f), 0);
-	}
-	if (filename)
-		free(filename);
-	uci_close_stream(f);
-	ctx->errno = 0;
-}
-
 
 static char *uci_config_path(struct uci_context *ctx, const char *name)
 {
 	char *filename;
 
-	if (strchr(name, '/'))
-		UCI_THROW(ctx, UCI_ERR_INVAL);
-	filename = uci_malloc(ctx, strlen(name) + sizeof(UCI_CONFDIR) + 2);
-	sprintf(filename, UCI_CONFDIR "/%s", name);
+	UCI_ASSERT(ctx, uci_validate_package(name));
+	filename = uci_malloc(ctx, strlen(name) + strlen(ctx->confdir) + 2);
+	sprintf(filename, "%s/%s", ctx->confdir, name);
 
 	return filename;
 }
 
-int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
+static void uci_file_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 {
-	char *filename;
-	bool confdir;
-	FILE *file = NULL;
-
-	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, uci_validate_name(name));
-
-	switch (name[0]) {
-	case '.':
-		/* relative path outside of /etc/config */
-		if (name[1] != '/')
-			UCI_THROW(ctx, UCI_ERR_NOTFOUND);
-		/* fall through */
-	case '/':
-		/* absolute path outside of /etc/config */
-		filename = uci_strdup(ctx, name);
-		name = strrchr(name, '/') + 1;
-		confdir = false;
-		break;
-	default:
-		/* config in /etc/config */
-		filename = uci_config_path(ctx, name);
-		confdir = true;
-		break;
-	}
-
-	file = uci_open_stream(ctx, filename, SEEK_SET, false, false);
-	ctx->errno = 0;
-	UCI_TRAP_SAVE(ctx, done);
-	UCI_INTERNAL(uci_import, ctx, file, name, package, true);
-	UCI_TRAP_RESTORE(ctx);
-
-	if (*package) {
-		(*package)->path = filename;
-		(*package)->confdir = confdir;
-		uci_load_history(ctx, *package, false);
-	}
-
-done:
-	uci_close_stream(file);
-	return ctx->errno;
-}
-
-int uci_save(struct uci_context *ctx, struct uci_package *p)
-{
-	FILE *f = NULL;
-	char *filename = NULL;
-	struct uci_element *e, *tmp;
-
-	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, p != NULL);
-
-	/* 
-	 * if the config file was outside of the /etc/config path,
-	 * don't save the history to a file, update the real file
-	 * directly.
-	 * does not modify the uci_package pointer
-	 */
-	if (!p->confdir)
-		return uci_commit(ctx, &p, false);
-
-	if (uci_list_empty(&p->history))
-		return 0;
-
-	if ((asprintf(&filename, "%s/%s", UCI_SAVEDIR, p->e.name) < 0) || !filename)
-		UCI_THROW(ctx, UCI_ERR_MEM);
-
-	ctx->errno = 0;
-	UCI_TRAP_SAVE(ctx, done);
-	f = uci_open_stream(ctx, filename, SEEK_END, true, true);
-	UCI_TRAP_RESTORE(ctx);
-
-	uci_foreach_element_safe(&p->history, tmp, e) {
-		struct uci_history *h = uci_to_history(e);
-
-		if (h->cmd == UCI_CMD_REMOVE)
-			fprintf(f, "-");
-		else if (h->cmd == UCI_CMD_RENAME)
-			fprintf(f, "@");
-
-		fprintf(f, "%s.%s", p->e.name, h->section);
-		if (e->name)
-			fprintf(f, ".%s", e->name);
-
-		if (h->cmd == UCI_CMD_REMOVE)
-			fprintf(f, "\n");
-		else
-			fprintf(f, "=%s\n", h->value);
-		uci_free_history(h);
-	}
-
-done:
-	uci_close_stream(f);
-	if (filename)
-		free(filename);
-	if (ctx->errno)
-		UCI_THROW(ctx, ctx->errno);
-
-	return 0;
-}
-
-int uci_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
-{
-	struct uci_package *p;
-	FILE *f = NULL;
+	struct uci_package *p = *package;
+	FILE *f1, *f2 = NULL;
 	char *name = NULL;
 	char *path = NULL;
+	char *filename = NULL;
+	struct stat statbuf;
+	bool do_rename = false;
 
-	UCI_HANDLE_ERR(ctx);
-	UCI_ASSERT(ctx, package != NULL);
-	p = *package;
-
-	UCI_ASSERT(ctx, p != NULL);
 	if (!p->path) {
 		if (overwrite)
 			p->path = uci_config_path(ctx, p->e.name);
@@ -895,57 +723,81 @@ int uci_commit(struct uci_context *ctx, struct uci_package **package, bool overw
 			UCI_THROW(ctx, UCI_ERR_INVAL);
 	}
 
+	if ((asprintf(&filename, "%s/.%s.uci-XXXXXX", ctx->confdir, p->e.name) < 0) || !filename)
+		UCI_THROW(ctx, UCI_ERR_MEM);
+
+	if (!mktemp(filename))
+		*filename = 0;
+
+	if (!*filename) {
+		free(filename);
+		UCI_THROW(ctx, UCI_ERR_IO);
+	}
+
+	if ((stat(filename, &statbuf) == 0) && ((statbuf.st_mode & S_IFMT) != S_IFREG))
+		UCI_THROW(ctx, UCI_ERR_IO);
 
 	/* open the config file for writing now, so that it is locked */
-	f = uci_open_stream(ctx, p->path, SEEK_SET, true, true);
+	f1 = uci_open_stream(ctx, p->path, NULL, SEEK_SET, true, true);
 
-	/* flush unsaved changes and reload from history file */
+	/* flush unsaved changes and reload from delta file */
 	UCI_TRAP_SAVE(ctx, done);
-	if (p->confdir) {
+	if (p->has_delta) {
 		if (!overwrite) {
 			name = uci_strdup(ctx, p->e.name);
 			path = uci_strdup(ctx, p->path);
-			if (!uci_list_empty(&p->history))
+			/* dump our own changes to the delta file */
+			if (!uci_list_empty(&p->delta))
 				UCI_INTERNAL(uci_save, ctx, p);
+
+			/*
+			 * other processes might have modified the config
+			 * as well. dump and reload
+			 */
 			uci_free_package(&p);
-			uci_file_cleanup(ctx);
-			UCI_INTERNAL(uci_import, ctx, f, name, &p, true);
+			uci_cleanup(ctx);
+			UCI_INTERNAL(uci_import, ctx, f1, name, &p, true);
 
 			p->path = path;
-			p->confdir = true;
+			p->has_delta = true;
 			*package = p;
 
 			/* freed together with the uci_package */
 			path = NULL;
-
-			/* check for updated history, just in case */
-			uci_load_history(ctx, p, true);
-		} else {
-			/* flush history */
-			uci_load_history(ctx, NULL, true);
 		}
+
+		/* flush delta */
+		if (!uci_load_delta(ctx, p, true))
+			goto done;
 	}
 
-	rewind(f);
-	ftruncate(fileno(f), 0);
+	f2 = uci_open_stream(ctx, filename, p->path, SEEK_SET, true, true);
+	uci_export(ctx, f2, p, false);
+
+	fflush(f2);
+	fsync(fileno(f2));
+	uci_close_stream(f2);
+
+	do_rename = true;
 
-	uci_export(ctx, f, p, false);
 	UCI_TRAP_RESTORE(ctx);
 
 done:
-	if (name)
-		free(name);
-	if (path)
-		free(path);
-	uci_close_stream(f);
-	if (ctx->errno)
-		UCI_THROW(ctx, ctx->errno);
-
-	return 0;
+	free(name);
+	free(path);
+	uci_close_stream(f1);
+	if (do_rename && rename(filename, p->path)) {
+		unlink(filename);
+		UCI_THROW(ctx, UCI_ERR_IO);
+	}
+	free(filename);
+	sync();
+	if (ctx->err)
+		UCI_THROW(ctx, ctx->err);
 }
 
 
-/* 
+/*
  * This function returns the filename by returning the string
  * after the last '/' character. By checking for a non-'\0'
  * character afterwards, directories are ignored (glob marks
@@ -962,17 +814,20 @@ static inline char *get_filename(char *path)
 	return p;
 }
 
-int uci_list_configs(struct uci_context *ctx, char ***list)
+static char **uci_list_config_files(struct uci_context *ctx)
 {
 	char **configs;
 	glob_t globbuf;
 	int size, i;
 	char *buf;
+	char *dir;
 
-	UCI_HANDLE_ERR(ctx);
-
-	if (glob(UCI_CONFDIR "/*", GLOB_MARK, NULL, &globbuf) != 0)
+	dir = uci_malloc(ctx, strlen(ctx->confdir) + 1 + sizeof("/*"));
+	sprintf(dir, "%s/*", ctx->confdir);
+	if (glob(dir, GLOB_MARK, NULL, &globbuf) != 0) {
+		free(dir);
 		UCI_THROW(ctx, UCI_ERR_NOTFOUND);
+	}
 
 	size = sizeof(char *) * (globbuf.gl_pathc + 1);
 	for(i = 0; i < globbuf.gl_pathc; i++) {
@@ -994,12 +849,67 @@ int uci_list_configs(struct uci_context *ctx, char ***list)
 		if (!p)
 			continue;
 
+		if (!uci_validate_package(p))
+			continue;
+
 		configs[i] = buf;
 		strcpy(buf, p);
 		buf += strlen(buf) + 1;
 	}
-	*list = configs;
+	free(dir);
+	globfree(&globbuf);
+	return configs;
+}
 
-	return 0;
+static struct uci_package *uci_file_load(struct uci_context *ctx, const char *name)
+{
+	struct uci_package *package = NULL;
+	char *filename;
+	bool confdir;
+	FILE *file = NULL;
+
+	switch (name[0]) {
+	case '.':
+		/* relative path outside of /etc/config */
+		if (name[1] != '/')
+			UCI_THROW(ctx, UCI_ERR_NOTFOUND);
+		/* fall through */
+	case '/':
+		/* absolute path outside of /etc/config */
+		filename = uci_strdup(ctx, name);
+		name = strrchr(name, '/') + 1;
+		confdir = false;
+		break;
+	default:
+		/* config in /etc/config */
+		filename = uci_config_path(ctx, name);
+		confdir = true;
+		break;
+	}
+
+	UCI_TRAP_SAVE(ctx, done);
+	file = uci_open_stream(ctx, filename, NULL, SEEK_SET, false, false);
+	ctx->err = 0;
+	UCI_INTERNAL(uci_import, ctx, file, name, &package, true);
+	UCI_TRAP_RESTORE(ctx);
+
+	if (package) {
+		package->path = filename;
+		package->has_delta = confdir;
+		uci_load_delta(ctx, package, false);
+	}
+
+done:
+	uci_close_stream(file);
+	if (ctx->err) {
+		free(filename);
+		UCI_THROW(ctx, ctx->err);
+	}
+	return package;
 }
 
+__private UCI_BACKEND(uci_file_backend, "file",
+	.load = uci_file_load,
+	.commit = uci_file_commit,
+	.list_configs = uci_list_config_files,
+);