parser.c revision 4f6e8d7a00cbeda1e70cc15be9c4af1018bdad53 
1#include <stdio.h>
2#include <stdlib.h>
3#include <unistd.h>
4#include <fcntl.h>
5#include <stdarg.h>
6#include <string.h>
7#include <stddef.h>
8#include <ctype.h>
9
10#include "init.h"
11#include "property_service.h"
12
13#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
14#include <sys/_system_properties.h>
15
16static list_declare(service_list);
17static list_declare(action_list);
18static list_declare(action_queue);
19
20#define RAW(x...) log_write(6, x)
21
22void DUMP(void)
23{
24#if 0
25    struct service *svc;
26    struct action *act;
27    struct command *cmd;
28    struct listnode *node;
29    struct listnode *node2;
30    struct socketinfo *si;
31    int n;
32
33    list_for_each(node, &service_list) {
34        svc = node_to_item(node, struct service, slist);
35        RAW("service %s\n", svc->name);
36        RAW("  class '%s'\n", svc->classname);
37        RAW("  exec");
38        for (n = 0; n < svc->nargs; n++) {
39            RAW(" '%s'", svc->args[n]);
40        }
41        RAW("\n");
42        for (si = svc->sockets; si; si = si->next) {
43            RAW("  socket %s %s 0%o\n", si->name, si->type, si->perm);
44        }
45    }
46
47    list_for_each(node, &action_list) {
48        act = node_to_item(node, struct action, alist);
49        RAW("on %s\n", act->name);
50        list_for_each(node2, &act->commands) {
51            cmd = node_to_item(node2, struct command, clist);
52            RAW("  %p", cmd->func);
53            for (n = 0; n < cmd->nargs; n++) {
54                RAW(" %s", cmd->args[n]);
55            }
56            RAW("\n");
57        }
58        RAW("\n");
59    }
60#endif
61}
62
63#define MAXARGS 64
64
65#define T_EOF 0
66#define T_TEXT 1
67#define T_NEWLINE 2
68
69struct parse_state
70{
71    char *ptr;
72    char *text;
73    int line;
74    int nexttoken;
75    void *context;
76    void (*parse_line)(struct parse_state *state, int nargs, char **args);
77    const char *filename;
78};
79
80static void *parse_service(struct parse_state *state, int nargs, char **args);
81static void parse_line_service(struct parse_state *state, int nargs, char **args);
82
83static void *parse_action(struct parse_state *state, int nargs, char **args);
84static void parse_line_action(struct parse_state *state, int nargs, char **args);
85
86void parse_error(struct parse_state *state, const char *fmt, ...)
87{
88    va_list ap;
89    char buf[128];
90    int off;
91
92    snprintf(buf, 128, "%s: %d: ", state->filename, state->line);
93    buf[127] = 0;
94    off = strlen(buf);
95
96    va_start(ap, fmt);
97    vsnprintf(buf + off, 128 - off, fmt, ap);
98    va_end(ap);
99    buf[127] = 0;
100    ERROR("%s", buf);
101}
102
103#define SECTION 0x01
104#define COMMAND 0x02
105#define OPTION  0x04
106
107#include "keywords.h"
108
109#define KEYWORD(symbol, flags, nargs, func) \
110    [ K_##symbol ] = { #symbol, func, nargs + 1, flags, },
111
112struct {
113    const char *name;
114    int (*func)(int nargs, char **args);
115    unsigned char nargs;
116    unsigned char flags;
117} keyword_info[KEYWORD_COUNT] = {
118    [ K_UNKNOWN ] = { "unknown", 0, 0, 0 },
119#include "keywords.h"
120};
121#undef KEYWORD
122
123#define kw_is(kw, type) (keyword_info[kw].flags & (type))
124#define kw_name(kw) (keyword_info[kw].name)
125#define kw_func(kw) (keyword_info[kw].func)
126#define kw_nargs(kw) (keyword_info[kw].nargs)
127
128int lookup_keyword(const char *s)
129{
130    switch (*s++) {
131    case 'c':
132        if (!strcmp(s, "apability")) return K_capability;
133        if (!strcmp(s, "lass")) return K_class;
134        if (!strcmp(s, "lass_start")) return K_class_start;
135        if (!strcmp(s, "lass_stop")) return K_class_stop;
136        if (!strcmp(s, "onsole")) return K_console;
137        if (!strcmp(s, "hown")) return K_chown;
138        if (!strcmp(s, "hmod")) return K_chmod;
139        if (!strcmp(s, "ritical")) return K_critical;
140        break;
141    case 'd':
142        if (!strcmp(s, "isabled")) return K_disabled;
143        if (!strcmp(s, "omainname")) return K_domainname;
144        if (!strcmp(s, "evice")) return K_device;
145        break;
146    case 'e':
147        if (!strcmp(s, "xec")) return K_exec;
148        if (!strcmp(s, "xport")) return K_export;
149        break;
150    case 'g':
151        if (!strcmp(s, "roup")) return K_group;
152        break;
153    case 'h':
154        if (!strcmp(s, "ostname")) return K_hostname;
155        break;
156    case 'i':
157        if (!strcmp(s, "fup")) return K_ifup;
158        if (!strcmp(s, "nsmod")) return K_insmod;
159        if (!strcmp(s, "mport")) return K_import;
160        break;
161    case 'l':
162        if (!strcmp(s, "oglevel")) return K_loglevel;
163        break;
164    case 'm':
165        if (!strcmp(s, "kdir")) return K_mkdir;
166        if (!strcmp(s, "ount")) return K_mount;
167        break;
168    case 'o':
169        if (!strcmp(s, "n")) return K_on;
170        if (!strcmp(s, "neshot")) return K_oneshot;
171        if (!strcmp(s, "nrestart")) return K_onrestart;
172        break;
173    case 'r':
174        if (!strcmp(s, "estart")) return K_restart;
175        break;
176    case 's':
177        if (!strcmp(s, "ervice")) return K_service;
178        if (!strcmp(s, "etenv")) return K_setenv;
179        if (!strcmp(s, "etkey")) return K_setkey;
180        if (!strcmp(s, "etprop")) return K_setprop;
181        if (!strcmp(s, "etrlimit")) return K_setrlimit;
182        if (!strcmp(s, "ocket")) return K_socket;
183        if (!strcmp(s, "tart")) return K_start;
184        if (!strcmp(s, "top")) return K_stop;
185        if (!strcmp(s, "ymlink")) return K_symlink;
186        break;
187    case 't':
188        if (!strcmp(s, "rigger")) return K_trigger;
189        break;
190    case 'u':
191        if (!strcmp(s, "ser")) return K_user;
192        break;
193    case 'w':
194        if (!strcmp(s, "rite")) return K_write;
195        break;
196    }
197    return K_UNKNOWN;
198}
199
200void parse_line_no_op(struct parse_state *state, int nargs, char **args)
201{
202}
203
204int next_token(struct parse_state *state)
205{
206    char *x = state->ptr;
207    char *s;
208
209    if (state->nexttoken) {
210        int t = state->nexttoken;
211        state->nexttoken = 0;
212        return t;
213    }
214
215    for (;;) {
216        switch (*x) {
217        case 0:
218            state->ptr = x;
219            return T_EOF;
220        case '\n':
221            state->line++;
222            x++;
223            state->ptr = x;
224            return T_NEWLINE;
225        case ' ':
226        case '\t':
227        case '\r':
228            x++;
229            continue;
230        case '#':
231            while (*x && (*x != '\n')) x++;
232            state->line++;
233            state->ptr = x;
234            return T_NEWLINE;
235        default:
236            goto text;
237        }
238    }
239
240textdone:
241    state->ptr = x;
242    *s = 0;
243    return T_TEXT;
244text:
245    state->text = s = x;
246textresume:
247    for (;;) {
248        switch (*x) {
249        case 0:
250            goto textdone;
251        case ' ':
252        case '\t':
253        case '\r':
254            x++;
255            goto textdone;
256        case '\n':
257            state->nexttoken = T_NEWLINE;
258            x++;
259            goto textdone;
260        case '"':
261            x++;
262            for (;;) {
263                switch (*x) {
264                case 0:
265                        /* unterminated quoted thing */
266                    state->ptr = x;
267                    return T_EOF;
268                case '"':
269                    x++;
270                    goto textresume;
271                default:
272                    *s++ = *x++;
273                }
274            }
275            break;
276        case '\\':
277            x++;
278            switch (*x) {
279            case 0:
280                goto textdone;
281            case 'n':
282                *s++ = '\n';
283                break;
284            case 'r':
285                *s++ = '\r';
286                break;
287            case 't':
288                *s++ = '\t';
289                break;
290            case '\\':
291                *s++ = '\\';
292                break;
293            case '\r':
294                    /* \ <cr> <lf> -> line continuation */
295                if (x[1] != '\n') {
296                    x++;
297                    continue;
298                }
299            case '\n':
300                    /* \ <lf> -> line continuation */
301                state->line++;
302                x++;
303                    /* eat any extra whitespace */
304                while((*x == ' ') || (*x == '\t')) x++;
305                continue;
306            default:
307                    /* unknown escape -- just copy */
308                *s++ = *x++;
309            }
310            continue;
311        default:
312            *s++ = *x++;
313        }
314    }
315    return T_EOF;
316}
317
318void parse_line(int nargs, char **args)
319{
320    int n;
321    int id = lookup_keyword(args[0]);
322    printf("%s(%d)", args[0], id);
323    for (n = 1; n < nargs; n++) {
324        printf(" '%s'", args[n]);
325    }
326    printf("\n");
327}
328
329void parse_new_section(struct parse_state *state, int kw,
330                       int nargs, char **args)
331{
332    printf("[ %s %s ]\n", args[0],
333           nargs > 1 ? args[1] : "");
334    switch(kw) {
335    case K_service:
336        state->context = parse_service(state, nargs, args);
337        if (state->context) {
338            state->parse_line = parse_line_service;
339            return;
340        }
341        break;
342    case K_on:
343        state->context = parse_action(state, nargs, args);
344        if (state->context) {
345            state->parse_line = parse_line_action;
346            return;
347        }
348        break;
349    }
350    state->parse_line = parse_line_no_op;
351}
352
353static void parse_config(const char *fn, char *s)
354{
355    struct parse_state state;
356    char *args[MAXARGS];
357    int nargs;
358
359    nargs = 0;
360    state.filename = fn;
361    state.line = 1;
362    state.ptr = s;
363    state.nexttoken = 0;
364    state.parse_line = parse_line_no_op;
365    for (;;) {
366        switch (next_token(&state)) {
367        case T_EOF:
368            state.parse_line(&state, 0, 0);
369            return;
370        case T_NEWLINE:
371            if (nargs) {
372                int kw = lookup_keyword(args[0]);
373                if (kw_is(kw, SECTION)) {
374                    state.parse_line(&state, 0, 0);
375                    parse_new_section(&state, kw, nargs, args);
376                } else {
377                    state.parse_line(&state, nargs, args);
378                }
379                nargs = 0;
380            }
381            break;
382        case T_TEXT:
383            if (nargs < MAXARGS) {
384                args[nargs++] = state.text;
385            }
386            break;
387        }
388    }
389}
390
391int parse_config_file(const char *fn)
392{
393    char *data;
394    data = read_file(fn, 0);
395    if (!data) return -1;
396
397    parse_config(fn, data);
398    DUMP();
399    return 0;
400}
401
402static int valid_name(const char *name)
403{
404    if (strlen(name) > 16) {
405        return 0;
406    }
407    while (*name) {
408        if (!isalnum(*name) && (*name != '_') && (*name != '-')) {
409            return 0;
410        }
411        name++;
412    }
413    return 1;
414}
415
416struct service *service_find_by_name(const char *name)
417{
418    struct listnode *node;
419    struct service *svc;
420    list_for_each(node, &service_list) {
421        svc = node_to_item(node, struct service, slist);
422        if (!strcmp(svc->name, name)) {
423            return svc;
424        }
425    }
426    return 0;
427}
428
429struct service *service_find_by_pid(pid_t pid)
430{
431    struct listnode *node;
432    struct service *svc;
433    list_for_each(node, &service_list) {
434        svc = node_to_item(node, struct service, slist);
435        if (svc->pid == pid) {
436            return svc;
437        }
438    }
439    return 0;
440}
441
442void service_for_each_class(const char *classname,
443                            void (*func)(struct service *svc))
444{
445    struct listnode *node;
446    struct service *svc;
447    list_for_each(node, &service_list) {
448        svc = node_to_item(node, struct service, slist);
449        if (!strcmp(svc->classname, classname)) {
450            func(svc);
451        }
452    }
453}
454
455void service_for_each_flags(unsigned matchflags,
456                            void (*func)(struct service *svc))
457{
458    struct listnode *node;
459    struct service *svc;
460    list_for_each(node, &service_list) {
461        svc = node_to_item(node, struct service, slist);
462        if (svc->flags & matchflags) {
463            func(svc);
464        }
465    }
466}
467
468void action_for_each_trigger(const char *trigger,
469                             void (*func)(struct action *act))
470{
471    struct listnode *node;
472    struct action *act;
473    list_for_each(node, &action_list) {
474        act = node_to_item(node, struct action, alist);
475        if (!strcmp(act->name, trigger)) {
476            func(act);
477        }
478    }
479}
480
481void queue_property_triggers(const char *name, const char *value)
482{
483    struct listnode *node;
484    struct action *act;
485    list_for_each(node, &action_list) {
486        act = node_to_item(node, struct action, alist);
487        if (!strncmp(act->name, "property:", strlen("property:"))) {
488            const char *test = act->name + strlen("property:");
489            int name_length = strlen(name);
490
491            if (!strncmp(name, test, name_length) &&
492                    test[name_length] == '=' &&
493                    !strcmp(test + name_length + 1, value)) {
494                action_add_queue_tail(act);
495            }
496        }
497    }
498}
499
500void queue_all_property_triggers()
501{
502    struct listnode *node;
503    struct action *act;
504    list_for_each(node, &action_list) {
505        act = node_to_item(node, struct action, alist);
506        if (!strncmp(act->name, "property:", strlen("property:"))) {
507            /* parse property name and value
508               syntax is property:<name>=<value> */
509            const char* name = act->name + strlen("property:");
510            const char* equals = strchr(name, '=');
511            if (equals) {
512                char* prop_name[PROP_NAME_MAX + 1];
513                const char* value;
514                int length = equals - name;
515                if (length > PROP_NAME_MAX) {
516                    ERROR("property name too long in trigger %s", act->name);
517                } else {
518                    memcpy(prop_name, name, length);
519                    prop_name[length] = 0;
520
521                    /* does the property exist, and match the trigger value? */
522                    value = property_get((const char *)&prop_name[0]);
523                    if (value && !strcmp(equals + 1, value)) {
524                        action_add_queue_tail(act);
525                    }
526                }
527            }
528        }
529    }
530}
531
532void action_add_queue_tail(struct action *act)
533{
534    list_add_tail(&action_queue, &act->qlist);
535}
536
537struct action *action_remove_queue_head(void)
538{
539    if (list_empty(&action_queue)) {
540        return 0;
541    } else {
542        struct listnode *node = list_head(&action_queue);
543        struct action *act = node_to_item(node, struct action, qlist);
544        list_remove(node);
545        return act;
546    }
547}
548
549static void *parse_service(struct parse_state *state, int nargs, char **args)
550{
551    struct service *svc;
552    if (nargs < 3) {
553        parse_error(state, "services must have a name and a program\n");
554        return 0;
555    }
556    if (!valid_name(args[1])) {
557        parse_error(state, "invalid service name '%s'\n", args[1]);
558        return 0;
559    }
560
561    svc = service_find_by_name(args[1]);
562    if (svc) {
563        parse_error(state, "ignored duplicate definition of service '%s'\n", args[1]);
564        return 0;
565    }
566
567    nargs -= 2;
568    svc = calloc(1, sizeof(*svc) + sizeof(char*) * nargs);
569    if (!svc) {
570        parse_error(state, "out of memory\n");
571        return 0;
572    }
573    svc->name = args[1];
574    svc->classname = "default";
575    memcpy(svc->args, args + 2, sizeof(char*) * nargs);
576    svc->args[nargs] = 0;
577    svc->nargs = nargs;
578    svc->onrestart.name = "onrestart";
579    list_init(&svc->onrestart.commands);
580    list_add_tail(&service_list, &svc->slist);
581    return svc;
582}
583
584static void parse_line_service(struct parse_state *state, int nargs, char **args)
585{
586    struct service *svc = state->context;
587    struct command *cmd;
588    int kw, kw_nargs;
589
590    if (nargs == 0) {
591        return;
592    }
593
594    kw = lookup_keyword(args[0]);
595    switch (kw) {
596    case K_capability:
597        break;
598    case K_class:
599        if (nargs != 2) {
600            parse_error(state, "class option requires a classname\n");
601        } else {
602            svc->classname = args[1];
603        }
604        break;
605    case K_console:
606        svc->flags |= SVC_CONSOLE;
607        break;
608    case K_disabled:
609        svc->flags |= SVC_DISABLED;
610        break;
611    case K_group:
612        if (nargs < 2) {
613            parse_error(state, "group option requires a group id\n");
614        } else if (nargs > NR_SVC_SUPP_GIDS + 2) {
615            parse_error(state, "group option accepts at most %d supp. groups\n",
616                        NR_SVC_SUPP_GIDS);
617        } else {
618            int n;
619            svc->gid = decode_uid(args[1]);
620            for (n = 2; n < nargs; n++) {
621                svc->supp_gids[n-2] = decode_uid(args[n]);
622            }
623            svc->nr_supp_gids = n - 2;
624        }
625        break;
626    case K_oneshot:
627        svc->flags |= SVC_ONESHOT;
628        break;
629    case K_onrestart:
630        nargs--;
631        args++;
632        kw = lookup_keyword(args[0]);
633        if (!kw_is(kw, COMMAND)) {
634            parse_error(state, "invalid command '%s'\n", args[0]);
635            break;
636        }
637        kw_nargs = kw_nargs(kw);
638        if (nargs < kw_nargs) {
639            parse_error(state, "%s requires %d %s\n", args[0], kw_nargs - 1,
640                kw_nargs > 2 ? "arguments" : "argument");
641            break;
642        }
643
644        cmd = malloc(sizeof(*cmd) + sizeof(char*) * nargs);
645        cmd->func = kw_func(kw);
646        cmd->nargs = nargs;
647        memcpy(cmd->args, args, sizeof(char*) * nargs);
648        list_add_tail(&svc->onrestart.commands, &cmd->clist);
649        break;
650    case K_critical:
651        svc->flags |= SVC_CRITICAL;
652        break;
653    case K_setenv: { /* name value */
654        struct svcenvinfo *ei;
655        if (nargs < 2) {
656            parse_error(state, "setenv option requires name and value arguments\n");
657            break;
658        }
659        ei = calloc(1, sizeof(*ei));
660        if (!ei) {
661            parse_error(state, "out of memory\n");
662            break;
663        }
664        ei->name = args[1];
665        ei->value = args[2];
666        ei->next = svc->envvars;
667        svc->envvars = ei;
668        break;
669    }
670    case K_socket: {/* name type perm [ uid gid ] */
671        struct socketinfo *si;
672        if (nargs < 4) {
673            parse_error(state, "socket option requires name, type, perm arguments\n");
674            break;
675        }
676        if (strcmp(args[2],"dgram") && strcmp(args[2],"stream")) {
677            parse_error(state, "socket type must be 'dgram' or 'stream'\n");
678            break;
679        }
680        si = calloc(1, sizeof(*si));
681        if (!si) {
682            parse_error(state, "out of memory\n");
683            break;
684        }
685        si->name = args[1];
686        si->type = args[2];
687        si->perm = strtoul(args[3], 0, 8);
688        if (nargs > 4)
689            si->uid = decode_uid(args[4]);
690        if (nargs > 5)
691            si->gid = decode_uid(args[5]);
692        si->next = svc->sockets;
693        svc->sockets = si;
694        break;
695    }
696    case K_user:
697        if (nargs != 2) {
698            parse_error(state, "user option requires a user id\n");
699        } else {
700            svc->uid = decode_uid(args[1]);
701        }
702        break;
703    default:
704        parse_error(state, "invalid option '%s'\n", args[0]);
705    }
706}
707
708static void *parse_action(struct parse_state *state, int nargs, char **args)
709{
710    struct action *act;
711    if (nargs < 2) {
712        parse_error(state, "actions must have a trigger\n");
713        return 0;
714    }
715    if (nargs > 2) {
716        parse_error(state, "actions may not have extra parameters\n");
717        return 0;
718    }
719    act = calloc(1, sizeof(*act));
720    act->name = args[1];
721    list_init(&act->commands);
722    list_add_tail(&action_list, &act->alist);
723        /* XXX add to hash */
724    return act;
725}
726
727static void parse_line_action(struct parse_state* state, int nargs, char **args)
728{
729    struct command *cmd;
730    struct action *act = state->context;
731    int (*func)(int nargs, char **args);
732    int kw, n;
733
734    if (nargs == 0) {
735        return;
736    }
737
738    kw = lookup_keyword(args[0]);
739    if (!kw_is(kw, COMMAND)) {
740        parse_error(state, "invalid command '%s'\n", args[0]);
741        return;
742    }
743
744    n = kw_nargs(kw);
745    if (nargs < n) {
746        parse_error(state, "%s requires %d %s\n", args[0], n - 1,
747            n > 2 ? "arguments" : "argument");
748        return;
749    }
750    cmd = malloc(sizeof(*cmd) + sizeof(char*) * nargs);
751    cmd->func = kw_func(kw);
752    cmd->nargs = nargs;
753    memcpy(cmd->args, args, sizeof(char*) * nargs);
754    list_add_tail(&act->commands, &cmd->clist);
755}
756