diff options
Diffstat (limited to 'libcutils/config_utils.cpp')
| -rw-r--r-- | libcutils/config_utils.cpp | 328 |
1 files changed, 328 insertions, 0 deletions
diff --git a/libcutils/config_utils.cpp b/libcutils/config_utils.cpp new file mode 100644 index 000000000..a3af01a58 --- /dev/null +++ b/libcutils/config_utils.cpp @@ -0,0 +1,328 @@ +/* + * Copyright (C) 2007 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <cutils/config_utils.h> + +#include <string.h> +#include <ctype.h> +#include <stdlib.h> +#include <fcntl.h> +#include <unistd.h> + +#include <cutils/misc.h> + +cnode* config_node(const char *name, const char *value) +{ + cnode* node = static_cast<cnode*>(calloc(sizeof(cnode), 1)); + if(node) { + node->name = name ? name : ""; + node->value = value ? value : ""; + } + + return node; +} + +cnode* config_find(cnode *root, const char *name) +{ + cnode *node, *match = NULL; + + /* we walk the whole list, as we need to return the last (newest) entry */ + for(node = root->first_child; node; node = node->next) + if(!strcmp(node->name, name)) + match = node; + + return match; +} + +static cnode* _config_create(cnode *root, const char *name) +{ + cnode *node; + + node = config_node(name, NULL); + + if(root->last_child) + root->last_child->next = node; + else + root->first_child = node; + + root->last_child = node; + + return node; +} + +int config_bool(cnode *root, const char *name, int _default) +{ + cnode *node; + + node = config_find(root, name); + if(!node) + return _default; + + switch(node->value[0]) { + case 'y': + case 'Y': + case '1': + return 1; + default: + return 0; + } +} + +const char* config_str(cnode *root, const char *name, const char *_default) +{ + cnode *node; + + node = config_find(root, name); + if(!node) + return _default; + return node->value; +} + +void config_set(cnode *root, const char *name, const char *value) +{ + cnode *node; + + node = config_find(root, name); + if(node) + node->value = value; + else { + node = _config_create(root, name); + node->value = value; + } +} + +#define T_EOF 0 +#define T_TEXT 1 +#define T_DOT 2 +#define T_OBRACE 3 +#define T_CBRACE 4 + +typedef struct +{ + char *data; + char *text; + int len; + char next; +} cstate; + +static int _lex(cstate *cs, int value) +{ + char c; + char *s; + char *data; + + data = cs->data; + + if(cs->next != 0) { + c = cs->next; + cs->next = 0; + goto got_c; + } + +restart: + for(;;) { + c = *data++; + got_c: + if(isspace(c)) + continue; + + switch(c) { + case 0: + return T_EOF; + + case '#': + for(;;) { + switch(*data) { + case 0: + cs->data = data; + return T_EOF; + case '\n': + cs->data = data + 1; + goto restart; + default: + data++; + } + } + break; + + case '.': + cs->data = data; + return T_DOT; + + case '{': + cs->data = data; + return T_OBRACE; + + case '}': + cs->data = data; + return T_CBRACE; + + default: + s = data - 1; + + if(value) { + for(;;) { + if(*data == 0) { + cs->data = data; + break; + } + if(*data == '\n') { + cs->data = data + 1; + *data-- = 0; + break; + } + data++; + } + + /* strip trailing whitespace */ + while(data > s){ + if(!isspace(*data)) break; + *data-- = 0; + } + + goto got_text; + } else { + for(;;) { + if(isspace(*data)) { + *data = 0; + cs->data = data + 1; + goto got_text; + } + switch(*data) { + case 0: + cs->data = data; + goto got_text; + case '.': + case '{': + case '}': + cs->next = *data; + *data = 0; + cs->data = data + 1; + goto got_text; + default: + data++; + } + } + } + } + } + +got_text: + cs->text = s; + return T_TEXT; +} + +#if 0 +char *TOKENNAMES[] = { "EOF", "TEXT", "DOT", "OBRACE", "CBRACE" }; + +static int lex(cstate *cs, int value) +{ + int tok = _lex(cs, value); + printf("TOKEN(%d) %s %s\n", value, TOKENNAMES[tok], + tok == T_TEXT ? cs->text : ""); + return tok; +} +#else +#define lex(cs,v) _lex(cs,v) +#endif + +static int parse_expr(cstate *cs, cnode *node); + +static int parse_block(cstate *cs, cnode *node) +{ + for(;;){ + switch(lex(cs, 0)){ + case T_TEXT: + if(parse_expr(cs, node)) return -1; + continue; + + case T_CBRACE: + return 0; + + default: + return -1; + } + } +} + +static int parse_expr(cstate *cs, cnode *root) +{ + cnode *node; + + /* last token was T_TEXT */ + node = config_find(root, cs->text); + if(!node || *node->value) + node = _config_create(root, cs->text); + + for(;;) { + switch(lex(cs, 1)) { + case T_DOT: + if(lex(cs, 0) != T_TEXT) + return -1; + node = _config_create(node, cs->text); + continue; + + case T_TEXT: + node->value = cs->text; + return 0; + + case T_OBRACE: + return parse_block(cs, node); + + default: + return -1; + } + } +} + +void config_load(cnode *root, char *data) +{ + if(data != 0) { + cstate cs; + cs.data = data; + cs.next = 0; + + for(;;) { + switch(lex(&cs, 0)) { + case T_TEXT: + if(parse_expr(&cs, root)) + return; + break; + default: + return; + } + } + } +} + +void config_load_file(cnode *root, const char *fn) +{ + char* data = static_cast<char*>(load_file(fn, nullptr)); + config_load(root, data); + // TODO: deliberate leak :-/ +} + +void config_free(cnode *root) +{ + cnode *cur = root->first_child; + + while (cur) { + cnode *prev = cur; + config_free(cur); + cur = cur->next; + free(prev); + } +} |