[ashd.git] / lib / cf.c

/*
    ashd - A Sane HTTP Daemon
    Copyright (C) 2008  Fredrik Tolf <fredrik@dolda2000.com>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    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.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <glob.h>
#include <libgen.h>
#include <sys/socket.h>
#include <errno.h>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <utils.h>
#include <cf.h>
#include <mt.h>
#include <proc.h>
#include <log.h>

#define CH_SOCKET 0
#define CH_FORK 1

struct stdchild {
    int type;
    char **argv;
    char **envp;
    int fd;
    int agains;
};

static int parsefile(struct cfstate *s, FILE *in);
static void stdmerge(struct child *old, struct child *new);
static int stdhandle(struct child *ch, struct hthead *req, int fd, void (*chinit)(void *), void *idata);
static void stddestroy(struct child *ch);

static int doinclude(struct cfstate *s, char *spec)
{
    int rv, i;
    FILE *inc;
    glob_t globm;
    char *fbk, *dir, *fspec;

    rv = 0;
    fbk = s->file;
    if(spec[0] == '/') {
	fspec = spec;
    } else {
	dir = sstrdup(fbk);
	fspec = sprintf3("%s/%s", dirname(dir), spec);
	free(dir);
    }
    if(glob(fspec, 0, NULL, &globm))
	return(0);
    for(i = 0; i < globm.gl_pathc; i++) {
	if((inc = fopen(globm.gl_pathv[i], "r")) != NULL) {
	    s->file = globm.gl_pathv[i];
	    if(parsefile(s, inc)) {
		fclose(inc);
		rv = 1;
		goto out;
	    }
	    fclose(inc);
	    inc = NULL;
	}
    }
    
out:
    globfree(&globm);
    s->file = fbk;
    return(rv);
}

static int parsefile(struct cfstate *s, FILE *in)
{
    int i;
    char line[1024];
    int eof, argc;
    int ind, indst[80], indl;
    char *p, **w;
    
    s->lno = 0;
    indst[indl = 0] = 0;
    eof = 0;
    while(1) {
	if(fgets(line, sizeof(line), in) == NULL) {
	    eof = 1;
	    line[0] = 0;
	}
	s->lno++;
	if(line[0]) {
	    for(p = line + strlen(line) - 1; p >= line; p--) {
		if(isspace(*p))
		    *p = 0;
		else
		    break;
	    }
	}
	for(ind = 0, p = line; *p; p++) {
	    if(*p == ' ') {
		ind++;
	    } else if(*p == '\t') {
		ind = ind - (ind % 8) + 8;
	    } else {
		break;
	    }
	}
	if(!eof && (!*p || (*p == '#')))
	    continue;
	
    reindent:
	if(ind > indst[indl]) {
	    indst[++indl] = ind;
	    if(!s->expstart) {
		s->res = tokenize("start");
		if(yield())
		    return(1);
	    } else {
		s->expstart = 0;
	    }
	} else {
	    if(s->expstart) {
		s->res = tokenize("end");
		if(yield())
		    return(1);
		s->expstart = 0;
	    }
	    while(ind < indst[indl]) {
		indl--;
		s->res = tokenize("end");
		if(yield())
		    return(1);
	    }
	    if(ind > indst[indl]) {
		flog(LOG_WARNING, "%s:%i: unexpected indentation level", s->file, s->lno);
		goto reindent;
	    }
	}
	
	if(eof)
	    return(0);
	
	argc = calen(w = tokenize(line));
	if(argc < 1) {
	    /* Shouldn't happen, but... */
	    freeca(w);
	    continue;
	}
	
	if(indl == 0) {
	    if(!strcmp(w[0], "include")) {
		for(i = 1; i < argc; i++) {
		    if(doinclude(s, w[i])) {
			freeca(w);
			return(1);
		    }
		}
		freeca(w);
		continue;
	    }
	}
	
	if(!strcmp(w[0], "start") ||
	   !strcmp(w[0], "end") || 
	   !strcmp(w[0], "eof")) {
	    flog(LOG_WARNING, "%s:%i: illegal directive: %s", s->file, s->lno, w[0]);
	} else {
	    s->res = w;
	    if(yield())
		return(1);
	}
    }
}

static void parsefn(struct muth *mt, va_list args)
{
    vavar(struct cfstate *, s);
    vavar(FILE *, in);
    vavar(char *, file);
    
    s->file = sstrdup(file);
    if(parsefile(s, in))
	goto out;
    do {
	s->res = tokenize("eof");
    } while(!yield());
    
out:
    free(s->file);
}

char **getcfline(struct cfstate *s)
{
    freeca(s->argv);
    if(s->res == NULL)
	resume(s->pf, 0);
    s->argc = calen(s->argv = s->res);
    s->res = NULL;
    return(s->argv);
}

struct cfstate *mkcfparser(FILE *in, char *name)
{
    struct cfstate *s;
    
    omalloc(s);
    s->pf = mustart(parsefn, s, in, name);
    return(s);
}

void freecfparser(struct cfstate *s)
{
    resume(s->pf, -1);
    freeca(s->argv);
    freeca(s->res);
    free(s);
}

char *findstdconf(char *name)
{
    char *home, *path, *p, *p2, *t;
    
    if((home = getenv("HOME")) != NULL) {
	if(!access(t = sprintf2("%s/.ashd/etc/%s", home, name), R_OK))
	    return(t);
	free(t);
    }
    if((path = getenv("PATH")) != NULL) {
	path = sstrdup(path);
	for(p = strtok(path, ":"); p != NULL; p = strtok(NULL, ":")) {
	    if((p2 = strrchr(p, '/')) == NULL)
		continue;
	    *p2 = 0;
	    if(!access(t = sprintf2("%s/etc/%s", p, name), R_OK)) {
		free(path);
		return(t);
	    }
	    free(t);
	}
	free(path);
    }
    return(NULL);
}

struct child *newchild(char *name, struct chandler *iface, void *pdata)
{
    struct child *ch;
    
    omalloc(ch);
    ch->name = sstrdup(name);
    ch->iface = iface;
    ch->pdata = pdata;
    return(ch);
}

void freechild(struct child *ch)
{
    if(ch->iface->destroy != NULL)
	ch->iface->destroy(ch);
    if(ch->name != NULL)
	free(ch->name);
    free(ch);
}

void mergechildren(struct child *dst, struct child *src)
{
    struct child *ch1, *ch2;
    
    for(ch1 = dst; ch1 != NULL; ch1 = ch1->next) {
	for(ch2 = src; ch2 != NULL; ch2 = ch2->next) {
	    if(ch1->iface->merge && !strcmp(ch1->name, ch2->name)) {
		ch1->iface->merge(ch1, ch2);
		break;
	    }
	}
    }
}

void skipcfblock(struct cfstate *s)
{
    char **w;
    
    while(1) {
	w = getcfline(s);
	if(!strcmp(w[0], "end") || !strcmp(w[0], "eof"))
	    return;
    }
}

static struct chandler stdhandler = {
    .handle = stdhandle,
    .merge = stdmerge,
    .destroy = stddestroy,
};

static char **expandargs(struct stdchild *sd)
{
    int i;
    char **ret, *p, *p2, *p3, *np, *env;
    struct charbuf exp;
    
    ret = szmalloc(sizeof(*ret) * (calen(sd->argv) + 1));
    bufinit(exp);
    for(i = 0; sd->argv[i] != NULL; i++) {
	if((p = strchr(sd->argv[i], '$')) == NULL) {
	    ret[i] = sstrdup(sd->argv[i]);
	} else {
	    exp.d = 0;
	    for(p2 = sd->argv[i]; p != NULL; p2 = np, p = strchr(np, '$')) {
		bufcat(exp, p2, p - p2);
		if(p[1] == '{') {
		    if((p3 = strchr((p += 2), '}')) == NULL)
			break;
		    np = p3 + 1;
		} else {
		    for(p3 = ++p; *p3; p3++) {
			if(!(((*p3 >= 'a') && (*p3 <= 'z')) ||
			     ((*p3 >= 'A') && (*p3 <= 'Z')) ||
			     ((*p3 >= '0') && (*p3 <= '9')) ||
			     (*p3 == '_'))) {
			    break;
			}
		    }
		    np = p3;
		}
		char temp[(p3 - p) + 1];
		memcpy(temp, p, p3 - p);
		temp[p3 - p] = 0;
		if((env = getenv(temp)) != NULL)
		    bufcatstr(exp, env);
	    }
	    bufcatstr2(exp, np);
	    ret[i] = sstrdup(exp.b);
	}
    }
    ret[i] = NULL;
    buffree(exp);
    return(ret);
}

struct sidata {
    struct stdchild *sd;
    void (*sinit)(void *);
    void *sdata;
};

static void stdinit(void *data)
{
    struct sidata *d = data;
    int i;
	
    for(i = 0; d->sd->envp[i]; i += 2)
	putenv(sprintf2("%s=%s", d->sd->envp[i], d->sd->envp[i + 1]));
    if(d->sinit != NULL)
	d->sinit(d->sdata);
}

static int stdhandle(struct child *ch, struct hthead *req, int fd, void (*chinit)(void *), void *sdata)
{
    struct stdchild *sd = ch->pdata;
    int serr;
    char **args;
    struct sidata idat;
    
    if(sd->type == CH_SOCKET) {
	idat = (struct sidata) {.sd = sd, .sinit = chinit, .sdata = sdata};
	if(sd->fd < 0) {
	    args = expandargs(sd);
	    sd->fd = stdmkchild(args, stdinit, &idat);
	    freeca(args);
	}
	if(sendreq2(sd->fd, req, fd, MSG_NOSIGNAL | MSG_DONTWAIT)) {
	    serr = errno;
	    if((serr == EPIPE) || (serr == ECONNRESET)) {
		/* Assume that the child has crashed and restart it. */
		close(sd->fd);
		args = expandargs(sd);
		sd->fd = stdmkchild(args, stdinit, &idat);
		freeca(args);
		if(!sendreq2(sd->fd, req, fd, MSG_NOSIGNAL | MSG_DONTWAIT))
		    goto ok;
		serr = errno;
	    }
	    if(serr == EAGAIN) {
		if(sd->agains++ == 0)
		    flog(LOG_WARNING, "request to child %s denied due to buffer overload", ch->name);
	    } else {
		flog(LOG_ERR, "could not pass on request to child %s: %s", ch->name, strerror(serr));
		close(sd->fd);
		sd->fd = -1;
	    }
	    return(-1);
	}
    ok:
	if(sd->agains > 0) {
	    flog(LOG_WARNING, "%i requests to child %s were denied due to buffer overload", sd->agains, ch->name);
	    sd->agains = 0;
	}
    } else if(sd->type == CH_FORK) {
	args = expandargs(sd);
	if(stdforkserve(args, req, fd, chinit, sdata) < 0) {
	    freeca(args);
	    return(-1);
	}
	freeca(args);
    }
    return(0);
}

static void stdmerge(struct child *dst, struct child *src)
{
    struct stdchild *od, *nd;
    
    if(src->iface == &stdhandler) {
	nd = dst->pdata;
	od = src->pdata;
	nd->fd = od->fd;
	od->fd = -1;
    }
}

static void stddestroy(struct child *ch)
{
    struct stdchild *d = ch->pdata;
    
    if(d->fd >= 0)
	close(d->fd);
    if(d->argv)
	freeca(d->argv);
    if(d->envp)
	freeca(d->envp);
    free(d);
}

struct child *parsechild(struct cfstate *s)
{
    struct child *ch;
    struct stdchild *d;
    struct charvbuf envbuf;
    int i;
    int sl;
    
    sl = s->lno;
    if(!strcmp(s->argv[0], "child")) {
	s->expstart = 1;
	if(s->argc < 2) {
	    flog(LOG_WARNING, "%s:%i: missing name in child declaration", s->file, s->lno);
	    skipcfblock(s);
	    return(NULL);
	}
	ch = newchild(s->argv[1], &stdhandler, omalloc(d));
	d->type = CH_SOCKET;
    } else if(!strcmp(s->argv[0], "fchild")) {
	s->expstart = 1;
	if(s->argc < 2) {
	    flog(LOG_WARNING, "%s:%i: missing name in child declaration", s->file, s->lno);
	    skipcfblock(s);
	    return(NULL);
	}
	ch = newchild(s->argv[1], &stdhandler, omalloc(d));
	d->type = CH_FORK;
    } else {
	return(NULL);
    }
    d->fd = -1;
    
    bufinit(envbuf);
    while(1) {
	getcfline(s);
	if(!strcmp(s->argv[0], "exec")) {
	    if(s->argc < 2) {
		flog(LOG_WARNING, "%s:%i: too few parameters to `exec'", s->file, s->lno);
		continue;
	    }
	    d->argv = szmalloc(sizeof(*d->argv) * s->argc);
	    for(i = 0; i < s->argc - 1; i++)
		d->argv[i] = sstrdup(s->argv[i + 1]);
	} else if(!strcmp(s->argv[0], "env")) {
	    if(s->argc < 3) {
		flog(LOG_WARNING, "%s:%i: too few parameters to `env'", s->file, s->lno);
		continue;
	    }
	    bufadd(envbuf, sstrdup(s->argv[1]));
	    bufadd(envbuf, sstrdup(s->argv[2]));
	} else if(!strcmp(s->argv[0], "end") || !strcmp(s->argv[0], "eof")) {
	    break;
	} else {
	    flog(LOG_WARNING, "%s:%i: unknown directive `%s' in child declaration", s->file, s->lno, s->argv[0]);
	}
    }
    bufadd(envbuf, NULL);
    d->envp = envbuf.b;
    if(d->argv == NULL) {
	flog(LOG_WARNING, "%s:%i: missing `exec' in child declaration %s", s->file, sl, ch->name);
	freechild(ch);
	return(NULL);
    }
    return(ch);
}

int childhandle(struct child *ch, struct hthead *req, int fd, void (*chinit)(void *), void *idata)
{
    return(ch->iface->handle(ch, req, fd, chinit, idata));
}
Commit	Line	Data
06c1a718 FT	1	/*
	2	ashd - A Sane HTTP Daemon
	3	Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com>
	4
	5	This program is free software: you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License as published by
	7	the Free Software Foundation, either version 3 of the License, or
	8	(at your option) any later version.
	9
	10	This program is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	GNU General Public License for more details.
	14
	15	You should have received a copy of the GNU General Public License
	16	along with this program. If not, see <http://www.gnu.org/licenses/>.
	17	*/
	18
	19	#include <stdlib.h>
	20	#include <stdio.h>
	21	#include <unistd.h>
	22	#include <string.h>
	23	#include <ctype.h>
	24	#include <glob.h>
dd281054	25	#include <libgen.h>
3d74fc07	26	#include <sys/socket.h>
06c1a718 FT	27	#include <errno.h>
	28
	29	#ifdef HAVE_CONFIG_H
	30	#include <config.h>
	31	#endif
	32	#include <utils.h>
	33	#include <cf.h>
	34	#include <mt.h>
	35	#include <proc.h>
	36	#include <log.h>
	37
	38	#define CH_SOCKET 0
	39	#define CH_FORK 1
	40
1924fe8c FT	41	struct stdchild {
	42	int type;
	43	char **argv;
3b77f136	44	char **envp;
1924fe8c	45	int fd;
f2b4b031	46	int agains;
1924fe8c FT	47	};
1924fe8c FT	48
dd281054	49	static int parsefile(struct cfstate s, FILE in);
1924fe8c FT	50	static void stdmerge(struct child old, struct child new);
	51	static int stdhandle(struct child ch, struct hthead req, int fd, void (chinit)(void ), void *idata);
	52	static void stddestroy(struct child *ch);
dd281054 FT	53
dd281054 FT	54	static int doinclude(struct cfstate s, char spec)
06c1a718	55	{
dd281054 FT	56	int rv, i;
dd281054 FT	57	FILE *inc;
06c1a718	58	glob_t globm;
dd281054 FT	59	char fbk, dir, *fspec;
	60
	61	rv = 0;
	62	fbk = s->file;
	63	if(spec[0] == '/') {
	64	fspec = spec;
	65	} else {
	66	dir = sstrdup(fbk);
	67	fspec = sprintf3("%s/%s", dirname(dir), spec);
	68	free(dir);
	69	}
	70	if(glob(fspec, 0, NULL, &globm))
	71	return(0);
	72	for(i = 0; i < globm.gl_pathc; i++) {
	73	if((inc = fopen(globm.gl_pathv[i], "r")) != NULL) {
	74	s->file = globm.gl_pathv[i];
	75	if(parsefile(s, inc)) {
	76	fclose(inc);
	77	rv = 1;
	78	goto out;
	79	}
	80	fclose(inc);
	81	inc = NULL;
	82	}
	83	}
	84
	85	out:
	86	globfree(&globm);
	87	s->file = fbk;
	88	return(rv);
	89	}
	90
	91	static int parsefile(struct cfstate s, FILE in)
	92	{
	93	int i;
06c1a718 FT	94	char line[1024];
	95	int eof, argc;
	96	int ind, indst[80], indl;
dd281054	97	char p, *w;
06c1a718 FT	98
	99	s->lno = 0;
	100	indst[indl = 0] = 0;
	101	eof = 0;
	102	while(1) {
	103	if(fgets(line, sizeof(line), in) == NULL) {
	104	eof = 1;
	105	line[0] = 0;
	106	}
	107	s->lno++;
c3b91092 FT	108	if(line[0]) {
	109	for(p = line + strlen(line) - 1; p >= line; p--) {
	110	if(isspace(*p))
	111	*p = 0;
	112	else
	113	break;
	114	}
06c1a718 FT	115	}
	116	for(ind = 0, p = line; *p; p++) {
	117	if(*p == ' ') {
	118	ind++;
	119	} else if(*p == '\t') {
	120	ind = ind - (ind % 8) + 8;
	121	} else {
	122	break;
	123	}
	124	}
	125	if(!eof && (!p \|\| (p == '#')))
	126	continue;
	127
	128	reindent:
	129	if(ind > indst[indl]) {
	130	indst[++indl] = ind;
	131	if(!s->expstart) {
	132	s->res = tokenize("start");
	133	if(yield())
	134	return(1);
	135	} else {
	136	s->expstart = 0;
	137	}
	138	} else {
	139	if(s->expstart) {
	140	s->res = tokenize("end");
	141	if(yield())
	142	return(1);
	143	s->expstart = 0;
	144	}
	145	while(ind < indst[indl]) {
	146	indl--;
	147	s->res = tokenize("end");
	148	if(yield())
	149	return(1);
	150	}
	151	if(ind > indst[indl]) {
	152	flog(LOG_WARNING, "%s:%i: unexpected indentation level", s->file, s->lno);
	153	goto reindent;
	154	}
	155	}
	156
	157	if(eof)
	158	return(0);
	159
	160	argc = calen(w = tokenize(line));
	161	if(argc < 1) {
	162	/* Shouldn't happen, but... */
	163	freeca(w);
	164	continue;
	165	}
	166
	167	if(indl == 0) {
	168	if(!strcmp(w[0], "include")) {
06c1a718	169	for(i = 1; i < argc; i++) {
dd281054 FT	170	if(doinclude(s, w[i])) {
	171	freeca(w);
	172	return(1);
06c1a718 FT	173	}
	174	}
	175	freeca(w);
06c1a718 FT	176	continue;
	177	}
	178	}
	179
	180	if(!strcmp(w[0], "start") \|\|
	181	!strcmp(w[0], "end") \|\|
	182	!strcmp(w[0], "eof")) {
	183	flog(LOG_WARNING, "%s:%i: illegal directive: %s", s->file, s->lno, w[0]);
	184	} else {
	185	s->res = w;
	186	if(yield())
	187	return(1);
	188	}
	189	}
	190	}
	191
	192	static void parsefn(struct muth *mt, va_list args)
	193	{
	194	vavar(struct cfstate *, s);
	195	vavar(FILE *, in);
	196	vavar(char *, file);
	197
	198	s->file = sstrdup(file);
	199	if(parsefile(s, in))
	200	goto out;
	201	do {
	202	s->res = tokenize("eof");
	203	} while(!yield());
	204
	205	out:
	206	free(s->file);
	207	}
	208
	209	char *getcfline(struct cfstate s)
	210	{
	211	freeca(s->argv);
	212	if(s->res == NULL)
	213	resume(s->pf, 0);
	214	s->argc = calen(s->argv = s->res);
	215	s->res = NULL;
	216	return(s->argv);
	217	}
	218
	219	struct cfstate mkcfparser(FILE in, char *name)
	220	{
	221	struct cfstate *s;
	222
	223	omalloc(s);
	224	s->pf = mustart(parsefn, s, in, name);
	225	return(s);
	226	}
	227
	228	void freecfparser(struct cfstate *s)
	229	{
	230	resume(s->pf, -1);
	231	freeca(s->argv);
	232	freeca(s->res);
	233	free(s);
	234	}
	235
0fc6fd13 FT	236	char findstdconf(char name)
0fc6fd13 FT	237	{
f9a65eb2	238	char home, path, p, p2, *t;
0fc6fd13	239
f9a65eb2 FT	240	if((home = getenv("HOME")) != NULL) {
f9a65eb2 FT	241	if(!access(t = sprintf2("%s/.ashd/etc/%s", home, name), R_OK))
13975be5	242	return(t);
13975be5	243	free(t);
0fc6fd13	244	}
f9a65eb2 FT	245	if((path = getenv("PATH")) != NULL) {
	246	path = sstrdup(path);
	247	for(p = strtok(path, ":"); p != NULL; p = strtok(NULL, ":")) {
	248	if((p2 = strrchr(p, '/')) == NULL)
	249	continue;
	250	*p2 = 0;
	251	if(!access(t = sprintf2("%s/etc/%s", p, name), R_OK)) {
	252	free(path);
	253	return(t);
	254	}
	255	free(t);
	256	}
	257	free(path);
	258	}
0fc6fd13 FT	259	return(NULL);
	260	}
	261
1924fe8c	262	struct child newchild(char name, struct chandler iface, void pdata)
06c1a718 FT	263	{
	264	struct child *ch;
	265
	266	omalloc(ch);
	267	ch->name = sstrdup(name);
1924fe8c FT	268	ch->iface = iface;
1924fe8c FT	269	ch->pdata = pdata;
06c1a718 FT	270	return(ch);
	271	}
	272
	273	void freechild(struct child *ch)
	274	{
1924fe8c FT	275	if(ch->iface->destroy != NULL)
1924fe8c FT	276	ch->iface->destroy(ch);
06c1a718 FT	277	if(ch->name != NULL)
06c1a718 FT	278	free(ch->name);
06c1a718 FT	279	free(ch);
	280	}
	281
1924fe8c FT	282	void mergechildren(struct child dst, struct child src)
	283	{
	284	struct child ch1, ch2;
	285
	286	for(ch1 = dst; ch1 != NULL; ch1 = ch1->next) {
	287	for(ch2 = src; ch2 != NULL; ch2 = ch2->next) {
	288	if(ch1->iface->merge && !strcmp(ch1->name, ch2->name)) {
	289	ch1->iface->merge(ch1, ch2);
	290	break;
	291	}
	292	}
	293	}
	294	}
	295
06c1a718 FT	296	void skipcfblock(struct cfstate *s)
	297	{
	298	char **w;
	299
	300	while(1) {
	301	w = getcfline(s);
	302	if(!strcmp(w[0], "end") \|\| !strcmp(w[0], "eof"))
	303	return;
	304	}
	305	}
	306
1924fe8c FT	307	static struct chandler stdhandler = {
	308	.handle = stdhandle,
	309	.merge = stdmerge,
	310	.destroy = stddestroy,
	311	};
	312
b3eb750f FT	313	static char *expandargs(struct stdchild sd)
	314	{
	315	int i;
	316	char *ret, p, p2, p3, np, env;
	317	struct charbuf exp;
	318
	319	ret = szmalloc(sizeof(ret) (calen(sd->argv) + 1));
	320	bufinit(exp);
	321	for(i = 0; sd->argv[i] != NULL; i++) {
	322	if((p = strchr(sd->argv[i], '$')) == NULL) {
	323	ret[i] = sstrdup(sd->argv[i]);
	324	} else {
	325	exp.d = 0;
	326	for(p2 = sd->argv[i]; p != NULL; p2 = np, p = strchr(np, '$')) {
	327	bufcat(exp, p2, p - p2);
	328	if(p[1] == '{') {
	329	if((p3 = strchr((p += 2), '}')) == NULL)
	330	break;
	331	np = p3 + 1;
	332	} else {
	333	for(p3 = ++p; *p3; p3++) {
	334	if(!(((p3 >= 'a') && (p3 <= 'z')) \|\|
	335	((p3 >= 'A') && (p3 <= 'Z')) \|\|
	336	((p3 >= '0') && (p3 <= '9')) \|\|
	337	(*p3 == '_'))) {
	338	break;
	339	}
	340	}
	341	np = p3;
	342	}
	343	char temp[(p3 - p) + 1];
	344	memcpy(temp, p, p3 - p);
	345	temp[p3 - p] = 0;
	346	if((env = getenv(temp)) != NULL)
	347	bufcatstr(exp, env);
	348	}
	349	bufcatstr2(exp, np);
	350	ret[i] = sstrdup(exp.b);
	351	}
	352	}
	353	ret[i] = NULL;
	354	buffree(exp);
	355	return(ret);
	356	}
	357
091936b4 FT	358	struct sidata {
	359	struct stdchild *sd;
	360	void (sinit)(void );
	361	void *sdata;
	362	};
	363
	364	static void stdinit(void *data)
	365	{
	366	struct sidata *d = data;
	367	int i;
	368
	369	for(i = 0; d->sd->envp[i]; i += 2)
	370	putenv(sprintf2("%s=%s", d->sd->envp[i], d->sd->envp[i + 1]));
	371	if(d->sinit != NULL)
	372	d->sinit(d->sdata);
	373	}
	374
	375	static int stdhandle(struct child ch, struct hthead req, int fd, void (chinit)(void ), void *sdata)
1924fe8c	376	{
3b77f136	377	struct stdchild *sd = ch->pdata;
45b19d96	378	int serr;
b3eb750f	379	char **args;
091936b4	380	struct sidata idat;
3b77f136 FT	381
3b77f136 FT	382	if(sd->type == CH_SOCKET) {
7a092cef	383	idat = (struct sidata) {.sd = sd, .sinit = chinit, .sdata = sdata};
b3eb750f FT	384	if(sd->fd < 0) {
b3eb750f FT	385	args = expandargs(sd);
091936b4	386	sd->fd = stdmkchild(args, stdinit, &idat);
b3eb750f FT	387	freeca(args);
b3eb750f FT	388	}
3b77f136	389	if(sendreq2(sd->fd, req, fd, MSG_NOSIGNAL \| MSG_DONTWAIT)) {
45b19d96 FT	390	serr = errno;
45b19d96 FT	391	if((serr == EPIPE) \|\| (serr == ECONNRESET)) {
1924fe8c	392	/* Assume that the child has crashed and restart it. */
3b77f136	393	close(sd->fd);
b3eb750f	394	args = expandargs(sd);
091936b4	395	sd->fd = stdmkchild(args, stdinit, &idat);
b3eb750f	396	freeca(args);
3b77f136	397	if(!sendreq2(sd->fd, req, fd, MSG_NOSIGNAL \| MSG_DONTWAIT))
f2b4b031	398	goto ok;
6f761f0a	399	serr = errno;
1924fe8c	400	}
f2b4b031 FT	401	if(serr == EAGAIN) {
	402	if(sd->agains++ == 0)
	403	flog(LOG_WARNING, "request to child %s denied due to buffer overload", ch->name);
	404	} else {
82405659	405	flog(LOG_ERR, "could not pass on request to child %s: %s", ch->name, strerror(serr));
3b77f136 FT	406	close(sd->fd);
3b77f136 FT	407	sd->fd = -1;
fc35a3ef	408	}
1924fe8c FT	409	return(-1);
1924fe8c FT	410	}
f2b4b031 FT	411	ok:
	412	if(sd->agains > 0) {
	413	flog(LOG_WARNING, "%i requests to child %s were denied due to buffer overload", sd->agains, ch->name);
	414	sd->agains = 0;
	415	}
3b77f136	416	} else if(sd->type == CH_FORK) {
b3eb750f	417	args = expandargs(sd);
091936b4	418	if(stdforkserve(args, req, fd, chinit, sdata) < 0) {
b3eb750f	419	freeca(args);
1924fe8c	420	return(-1);
b3eb750f FT	421	}
b3eb750f FT	422	freeca(args);
1924fe8c FT	423	}
	424	return(0);
	425	}
	426
	427	static void stdmerge(struct child dst, struct child src)
	428	{
	429	struct stdchild od, nd;
	430
	431	if(src->iface == &stdhandler) {
	432	nd = dst->pdata;
	433	od = src->pdata;
	434	nd->fd = od->fd;
	435	od->fd = -1;
	436	}
	437	}
	438
	439	static void stddestroy(struct child *ch)
	440	{
	441	struct stdchild *d = ch->pdata;
	442
	443	if(d->fd >= 0)
	444	close(d->fd);
	445	if(d->argv)
	446	freeca(d->argv);
3b77f136 FT	447	if(d->envp)
3b77f136 FT	448	freeca(d->envp);
1924fe8c FT	449	free(d);
	450	}
	451
06c1a718 FT	452	struct child parsechild(struct cfstate s)
	453	{
	454	struct child *ch;
1924fe8c	455	struct stdchild *d;
3b77f136	456	struct charvbuf envbuf;
06c1a718 FT	457	int i;
	458	int sl;
	459
	460	sl = s->lno;
	461	if(!strcmp(s->argv[0], "child")) {
	462	s->expstart = 1;
	463	if(s->argc < 2) {
	464	flog(LOG_WARNING, "%s:%i: missing name in child declaration", s->file, s->lno);
	465	skipcfblock(s);
	466	return(NULL);
	467	}
1924fe8c FT	468	ch = newchild(s->argv[1], &stdhandler, omalloc(d));
1924fe8c FT	469	d->type = CH_SOCKET;
06c1a718 FT	470	} else if(!strcmp(s->argv[0], "fchild")) {
	471	s->expstart = 1;
	472	if(s->argc < 2) {
	473	flog(LOG_WARNING, "%s:%i: missing name in child declaration", s->file, s->lno);
	474	skipcfblock(s);
	475	return(NULL);
	476	}
1924fe8c FT	477	ch = newchild(s->argv[1], &stdhandler, omalloc(d));
1924fe8c FT	478	d->type = CH_FORK;
06c1a718 FT	479	} else {
	480	return(NULL);
	481	}
1924fe8c	482	d->fd = -1;
06c1a718	483
3b77f136	484	bufinit(envbuf);
06c1a718 FT	485	while(1) {
	486	getcfline(s);
	487	if(!strcmp(s->argv[0], "exec")) {
	488	if(s->argc < 2) {
	489	flog(LOG_WARNING, "%s:%i: too few parameters to `exec'", s->file, s->lno);
	490	continue;
	491	}
1924fe8c	492	d->argv = szmalloc(sizeof(d->argv) s->argc);
06c1a718	493	for(i = 0; i < s->argc - 1; i++)
1924fe8c	494	d->argv[i] = sstrdup(s->argv[i + 1]);
3b77f136 FT	495	} else if(!strcmp(s->argv[0], "env")) {
	496	if(s->argc < 3) {
	497	flog(LOG_WARNING, "%s:%i: too few parameters to `env'", s->file, s->lno);
	498	continue;
	499	}
	500	bufadd(envbuf, sstrdup(s->argv[1]));
	501	bufadd(envbuf, sstrdup(s->argv[2]));
06c1a718 FT	502	} else if(!strcmp(s->argv[0], "end") \|\| !strcmp(s->argv[0], "eof")) {
	503	break;
	504	} else {
	505	flog(LOG_WARNING, "%s:%i: unknown directive `%s' in child declaration", s->file, s->lno, s->argv[0]);
	506	}
	507	}
3b77f136 FT	508	bufadd(envbuf, NULL);
3b77f136 FT	509	d->envp = envbuf.b;
1924fe8c	510	if(d->argv == NULL) {
06c1a718 FT	511	flog(LOG_WARNING, "%s:%i: missing `exec' in child declaration %s", s->file, sl, ch->name);
	512	freechild(ch);
	513	return(NULL);
	514	}
	515	return(ch);
	516	}
	517
6a7a868e	518	int childhandle(struct child ch, struct hthead req, int fd, void (chinit)(void ), void *idata)
06c1a718	519	{
1924fe8c	520	return(ch->iface->handle(ch, req, fd, chinit, idata));
06c1a718	521	}