init_parser.cpp revision 4ad60fbae51ef4a0b4a4beaa5128d823063c158c 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <ctype.h>
18#include <dirent.h>
19#include <errno.h>
20#include <fcntl.h>
21#include <inttypes.h>
22#include <stdarg.h>
23#include <stddef.h>
24#include <stdio.h>
25#include <stdlib.h>
26#include <string.h>
27#include <unistd.h>
28
29#include "action.h"
30#include "init.h"
31#include "init_parser.h"
32#include "log.h"
33#include "parser.h"
34#include "property_service.h"
35#include "service.h"
36#include "util.h"
37
38#include <base/stringprintf.h>
39#include <cutils/iosched_policy.h>
40#include <cutils/list.h>
41
42static list_declare(service_list);
43
44struct import {
45    struct listnode list;
46    const char *filename;
47};
48
49static void *parse_service(struct parse_state *state, int nargs, char **args);
50static void parse_line_service(struct parse_state *state, int nargs, char **args);
51
52static void *parse_action(struct parse_state *state, int nargs, char **args);
53static void parse_line_action(struct parse_state *state, int nargs, char **args);
54
55#define SECTION 0x01
56#define COMMAND 0x02
57#define OPTION  0x04
58
59#include "keywords.h"
60
61#define KEYWORD(symbol, flags, nargs, func) \
62    [ K_##symbol ] = { #symbol, func, nargs + 1, flags, },
63
64static struct {
65    const char *name;
66    int (*func)(const std::vector<std::string>& args);
67    size_t nargs;
68    unsigned char flags;
69} keyword_info[KEYWORD_COUNT] = {
70    [ K_UNKNOWN ] = { "unknown", 0, 0, 0 },
71#include "keywords.h"
72};
73#undef KEYWORD
74
75#define kw_is(kw, type) (keyword_info[kw].flags & (type))
76#define kw_name(kw) (keyword_info[kw].name)
77#define kw_func(kw) (keyword_info[kw].func)
78#define kw_nargs(kw) (keyword_info[kw].nargs)
79
80void dump_parser_state() {
81    ServiceManager::GetInstance().DumpState();
82    ActionManager::GetInstance().DumpState();
83}
84
85static int lookup_keyword(const char *s)
86{
87    switch (*s++) {
88    case 'b':
89        if (!strcmp(s, "ootchart_init")) return K_bootchart_init;
90        break;
91    case 'c':
92        if (!strcmp(s, "opy")) return K_copy;
93        if (!strcmp(s, "lass")) return K_class;
94        if (!strcmp(s, "lass_start")) return K_class_start;
95        if (!strcmp(s, "lass_stop")) return K_class_stop;
96        if (!strcmp(s, "lass_reset")) return K_class_reset;
97        if (!strcmp(s, "onsole")) return K_console;
98        if (!strcmp(s, "hown")) return K_chown;
99        if (!strcmp(s, "hmod")) return K_chmod;
100        if (!strcmp(s, "ritical")) return K_critical;
101        break;
102    case 'd':
103        if (!strcmp(s, "isabled")) return K_disabled;
104        if (!strcmp(s, "omainname")) return K_domainname;
105        break;
106    case 'e':
107        if (!strcmp(s, "nable")) return K_enable;
108        if (!strcmp(s, "xec")) return K_exec;
109        if (!strcmp(s, "xport")) return K_export;
110        break;
111    case 'g':
112        if (!strcmp(s, "roup")) return K_group;
113        break;
114    case 'h':
115        if (!strcmp(s, "ostname")) return K_hostname;
116        break;
117    case 'i':
118        if (!strcmp(s, "oprio")) return K_ioprio;
119        if (!strcmp(s, "fup")) return K_ifup;
120        if (!strcmp(s, "nsmod")) return K_insmod;
121        if (!strcmp(s, "mport")) return K_import;
122        if (!strcmp(s, "nstallkey")) return K_installkey;
123        break;
124    case 'k':
125        if (!strcmp(s, "eycodes")) return K_keycodes;
126        break;
127    case 'l':
128        if (!strcmp(s, "oglevel")) return K_loglevel;
129        if (!strcmp(s, "oad_persist_props")) return K_load_persist_props;
130        if (!strcmp(s, "oad_all_props")) return K_load_all_props;
131        break;
132    case 'm':
133        if (!strcmp(s, "kdir")) return K_mkdir;
134        if (!strcmp(s, "ount_all")) return K_mount_all;
135        if (!strcmp(s, "ount")) return K_mount;
136        break;
137    case 'o':
138        if (!strcmp(s, "n")) return K_on;
139        if (!strcmp(s, "neshot")) return K_oneshot;
140        if (!strcmp(s, "nrestart")) return K_onrestart;
141        break;
142    case 'p':
143        if (!strcmp(s, "owerctl")) return K_powerctl;
144        break;
145    case 'r':
146        if (!strcmp(s, "estart")) return K_restart;
147        if (!strcmp(s, "estorecon")) return K_restorecon;
148        if (!strcmp(s, "estorecon_recursive")) return K_restorecon_recursive;
149        if (!strcmp(s, "mdir")) return K_rmdir;
150        if (!strcmp(s, "m")) return K_rm;
151        break;
152    case 's':
153        if (!strcmp(s, "eclabel")) return K_seclabel;
154        if (!strcmp(s, "ervice")) return K_service;
155        if (!strcmp(s, "etenv")) return K_setenv;
156        if (!strcmp(s, "etprop")) return K_setprop;
157        if (!strcmp(s, "etrlimit")) return K_setrlimit;
158        if (!strcmp(s, "ocket")) return K_socket;
159        if (!strcmp(s, "tart")) return K_start;
160        if (!strcmp(s, "top")) return K_stop;
161        if (!strcmp(s, "wapon_all")) return K_swapon_all;
162        if (!strcmp(s, "ymlink")) return K_symlink;
163        if (!strcmp(s, "ysclktz")) return K_sysclktz;
164        break;
165    case 't':
166        if (!strcmp(s, "rigger")) return K_trigger;
167        break;
168    case 'u':
169        if (!strcmp(s, "ser")) return K_user;
170        break;
171    case 'v':
172        if (!strcmp(s, "erity_load_state")) return K_verity_load_state;
173        if (!strcmp(s, "erity_update_state")) return K_verity_update_state;
174        break;
175    case 'w':
176        if (!strcmp(s, "rite")) return K_write;
177        if (!strcmp(s, "ritepid")) return K_writepid;
178        if (!strcmp(s, "ait")) return K_wait;
179        break;
180    }
181    return K_UNKNOWN;
182}
183
184static void parse_line_no_op(struct parse_state*, int, char**) {
185}
186
187int expand_props(const std::string& src, std::string* dst) {
188    const char *src_ptr = src.c_str();
189
190    if (!dst) {
191        return -1;
192    }
193
194    /* - variables can either be $x.y or ${x.y}, in case they are only part
195     *   of the string.
196     * - will accept $$ as a literal $.
197     * - no nested property expansion, i.e. ${foo.${bar}} is not supported,
198     *   bad things will happen
199     */
200    while (*src_ptr) {
201        const char *c;
202
203        c = strchr(src_ptr, '$');
204        if (!c) {
205            dst->append(src_ptr);
206            break;
207        }
208
209        dst->append(src_ptr, c);
210        c++;
211
212        if (*c == '$') {
213            dst->push_back(*(c++));
214            src_ptr = c;
215            continue;
216        } else if (*c == '\0') {
217            break;
218        }
219
220        std::string prop_name;
221        if (*c == '{') {
222            c++;
223            const char* end = strchr(c, '}');
224            if (!end) {
225                // failed to find closing brace, abort.
226                ERROR("unexpected end of string in '%s', looking for }\n", src.c_str());
227                goto err;
228            }
229            prop_name = std::string(c, end);
230            c = end + 1;
231        } else {
232            prop_name = c;
233            ERROR("using deprecated syntax for specifying property '%s', use ${name} instead\n",
234                  c);
235            c += prop_name.size();
236        }
237
238        if (prop_name.empty()) {
239            ERROR("invalid zero-length prop name in '%s'\n", src.c_str());
240            goto err;
241        }
242
243        std::string prop_val = property_get(prop_name.c_str());
244        if (prop_val.empty()) {
245            ERROR("property '%s' doesn't exist while expanding '%s'\n",
246                  prop_name.c_str(), src.c_str());
247            goto err;
248        }
249
250        dst->append(prop_val);
251        src_ptr = c;
252        continue;
253    }
254
255    return 0;
256err:
257    return -1;
258}
259
260static void parse_import(struct parse_state *state, int nargs, char **args)
261{
262    if (nargs != 2) {
263        ERROR("single argument needed for import\n");
264        return;
265    }
266
267    std::string conf_file;
268    int ret = expand_props(args[1], &conf_file);
269    if (ret) {
270        ERROR("error while handling import on line '%d' in '%s'\n",
271              state->line, state->filename);
272        return;
273    }
274
275    struct import* import = (struct import*) calloc(1, sizeof(struct import));
276    import->filename = strdup(conf_file.c_str());
277
278    struct listnode *import_list = (listnode*) state->priv;
279    list_add_tail(import_list, &import->list);
280    INFO("Added '%s' to import list\n", import->filename);
281}
282
283static void parse_new_section(struct parse_state *state, int kw,
284                       int nargs, char **args)
285{
286    printf("[ %s %s ]\n", args[0],
287           nargs > 1 ? args[1] : "");
288    switch(kw) {
289    case K_service:
290        state->context = parse_service(state, nargs, args);
291        if (state->context) {
292            state->parse_line = parse_line_service;
293            return;
294        }
295        break;
296    case K_on:
297        state->context = parse_action(state, nargs, args);
298        if (state->context) {
299            state->parse_line = parse_line_action;
300            return;
301        }
302        break;
303    case K_import:
304        parse_import(state, nargs, args);
305        break;
306    }
307    state->parse_line = parse_line_no_op;
308}
309
310static void parse_config(const char *fn, const std::string& data)
311{
312    struct listnode import_list;
313    struct listnode *node;
314    char *args[INIT_PARSER_MAXARGS];
315
316    int nargs = 0;
317
318    //TODO: Use a parser with const input and remove this copy
319    std::vector<char> data_copy(data.begin(), data.end());
320    data_copy.push_back('\0');
321
322    parse_state state;
323    state.filename = fn;
324    state.line = 0;
325    state.ptr = &data_copy[0];
326    state.nexttoken = 0;
327    state.parse_line = parse_line_no_op;
328
329    list_init(&import_list);
330    state.priv = &import_list;
331
332    for (;;) {
333        switch (next_token(&state)) {
334        case T_EOF:
335            state.parse_line(&state, 0, 0);
336            goto parser_done;
337        case T_NEWLINE:
338            state.line++;
339            if (nargs) {
340                int kw = lookup_keyword(args[0]);
341                if (kw_is(kw, SECTION)) {
342                    state.parse_line(&state, 0, 0);
343                    parse_new_section(&state, kw, nargs, args);
344                } else {
345                    state.parse_line(&state, nargs, args);
346                }
347                nargs = 0;
348            }
349            break;
350        case T_TEXT:
351            if (nargs < INIT_PARSER_MAXARGS) {
352                args[nargs++] = state.text;
353            }
354            break;
355        }
356    }
357
358parser_done:
359    list_for_each(node, &import_list) {
360         struct import* import = node_to_item(node, struct import, list);
361         if (!init_parse_config(import->filename)) {
362             ERROR("could not import file '%s' from '%s': %s\n",
363                   import->filename, fn, strerror(errno));
364         }
365    }
366}
367
368static bool init_parse_config_file(const char* path) {
369    INFO("Parsing file %s...\n", path);
370    Timer t;
371    std::string data;
372    if (!read_file(path, &data)) {
373        return false;
374    }
375
376    data.push_back('\n'); // TODO: fix parse_config.
377    parse_config(path, data);
378    dump_parser_state();
379
380    NOTICE("(Parsing %s took %.2fs.)\n", path, t.duration());
381    return true;
382}
383
384static bool init_parse_config_dir(const char* path) {
385    INFO("Parsing directory %s...\n", path);
386    std::unique_ptr<DIR, int(*)(DIR*)> config_dir(opendir(path), closedir);
387    if (!config_dir) {
388        ERROR("Could not import directory '%s'\n", path);
389        return false;
390    }
391    dirent* current_file;
392    while ((current_file = readdir(config_dir.get()))) {
393        std::string current_path =
394            android::base::StringPrintf("%s/%s", path, current_file->d_name);
395        // Ignore directories and only process regular files.
396        if (current_file->d_type == DT_REG) {
397            if (!init_parse_config_file(current_path.c_str())) {
398                ERROR("could not import file '%s'\n", current_path.c_str());
399            }
400        }
401    }
402    return true;
403}
404
405bool init_parse_config(const char* path) {
406    if (is_dir(path)) {
407        return init_parse_config_dir(path);
408    }
409    return init_parse_config_file(path);
410}
411
412static void *parse_service(struct parse_state *state, int nargs, char **args)
413{
414    if (nargs < 3) {
415        parse_error(state, "services must have a name and a program\n");
416        return nullptr;
417    }
418    std::vector<std::string> str_args(args + 2, args + nargs);
419    std::string ret_err;
420    Service* svc = ServiceManager::GetInstance().AddNewService(args[1], "default",
421                                                               str_args, &ret_err);
422
423    if (!svc) {
424        parse_error(state, "%s\n", ret_err.c_str());
425    }
426
427    return svc;
428}
429
430static void parse_line_service(struct parse_state *state, int nargs, char **args)
431{
432    if (nargs == 0) {
433        return;
434    }
435
436    Service* svc = static_cast<Service*>(state->context);
437    int kw = lookup_keyword(args[0]);
438    std::vector<std::string> str_args(args, args + nargs);
439    std::string ret_err;
440    bool ret = svc->HandleLine(kw, str_args, &ret_err);
441
442    if (!ret) {
443        parse_error(state, "%s\n", ret_err.c_str());
444    }
445}
446
447static void *parse_action(struct parse_state* state, int nargs, char **args)
448{
449    std::string ret_err;
450    std::vector<std::string> triggers(args + 1, args + nargs);
451    Action* ret = ActionManager::GetInstance().AddNewAction(triggers, &ret_err);
452
453    if (!ret) {
454        parse_error(state, "%s\n", ret_err.c_str());
455    }
456
457    return ret;
458}
459
460bool add_command_to_action(Action* action, const std::vector<std::string>& args,
461                           const std::string& filename, int line, std::string* err)
462{
463    int kw;
464    size_t n;
465
466    kw = lookup_keyword(args[0].c_str());
467    if (!kw_is(kw, COMMAND)) {
468        *err = android::base::StringPrintf("invalid command '%s'\n", args[0].c_str());
469        return false;
470    }
471
472    n = kw_nargs(kw);
473    if (args.size() < n) {
474        *err = android::base::StringPrintf("%s requires %zu %s\n",
475                                           args[0].c_str(), n - 1,
476                                           n > 2 ? "arguments" : "argument");
477        return false;
478    }
479
480    action->AddCommand(kw_func(kw), args, filename, line);
481    return true;
482}
483
484static void parse_line_action(struct parse_state* state, int nargs, char **args)
485{
486    if (nargs == 0) {
487        return;
488    }
489
490    Action* action = static_cast<Action*>(state->context);
491    std::vector<std::string> str_args(args, args + nargs);
492    std::string ret_err;
493    bool ret = add_command_to_action(action, str_args, state->filename,
494                                     state->line, &ret_err);
495    if (!ret) {
496        parse_error(state, "%s\n", ret_err.c_str());
497    }
498}
499