/*
   copyright (c) 2003 Peter Rockai (aka Yenar Calentaure) <yenar@platon.sk>
   covered by GNU LGPL

   implementation of DSN parser in C language
   created for libplaton on Nepto's request

   should pass all tests from PEAR for DB::ParseDSN
   to compare, run
   $ php4 db_parsedsn.phpt > php.out
   $ cc -DTEST parse_dsn.c -o parse_dsn && ./parse_dsn > c.out
   $ diff -u php.out c.out
   (note that DSN part after '?' is treated differently in C)

TODO: implement parsing of '?port=123&...' part this way:
parts that have counterpart in dsn_elements but would be
NULL othwerwise, should be used and removed from query

(un)known bugs -- valgrind reports:
Conditional jump or move depends on uninitialised value(s)
at 0x40166976: strlen (vg_clientfuncs.c:436)
by 0x80486CE: urldecode (parse_dsn.c:73)
by 0x8048A9E: parse_dsn (parse_dsn.c:160)
by 0x804907C: test (parse_dsn.c:286)
by 0x804933F: main (parse_dsn.c:326)
by 0x4023B14E: __libc_start_main (in /lib/libc-2.2.5.so)
by 0x8048510: (within /home/yenar/devel/utils/parseDSN/parse_dsn)
sheeh...
otherwise, code should be quite safe and leak-free

*/

#include <stdlib.h>
#include <string.h>

#include <platon/dsn/dsn.h>
#include <platon/str/strcgi.h>

	static void
dsn_free_ptr(ptr)
	char **ptr;
{
	if (*ptr != NULL) {
		free((void **) *ptr);
		*ptr = NULL;
	}
}

	void
dsn_free(el)
	struct dsn_elements *el;
{ /* {{{ */
	dsn_free_ptr(&(el->phptype));
	dsn_free_ptr(&(el->dbsyntax));
	dsn_free_ptr(&(el->username));
	dsn_free_ptr(&(el->password));
	dsn_free_ptr(&(el->protocol));
	dsn_free_ptr(&(el->hostspec));
	dsn_free_ptr(&(el->port));
	dsn_free_ptr(&(el->socket));
	dsn_free_ptr(&(el->database));
	dsn_free_ptr(&(el->query));
} /* }}} */

#define DSN_LEN(s)	(s == NULL ? 0 : strlen(s))

	char *
dsn_glue(el)
	const struct dsn_elements *el;
{ /* {{{ */
	register int len;
	register char *dsn;

	/* How much memory we have to allocate for DSN string */
	len = DSN_LEN(el->phptype)  + DSN_LEN(el->dbsyntax)
		+ DSN_LEN(el->username) + DSN_LEN(el->password)
		+ DSN_LEN(el->protocol) + DSN_LEN(el->hostspec)
		+ DSN_LEN(el->port)     + DSN_LEN(el->socket)
		+ DSN_LEN(el->database) + DSN_LEN(el->query);

	/* 30 characters is enough for element separators */
	if ((dsn = (char *) malloc((len + 30) * sizeof(char))) == NULL)
		return NULL; /* failure */

	/* Initialize DSN to empty string */
	*dsn = '\0';

	/* dbsyntax */
	if (el->dbsyntax != NULL) {
		strcat(dsn, el->dbsyntax);
	}
	/* phptype */
	if (el->phptype != NULL && strcmp(el->phptype, dsn)) {
		/* Who understands this will get one beer free on my own. :-) */
		memmove(dsn + strlen(el->phptype) + 1, dsn, strlen(dsn) + 1);
		strcpy(dsn, el->phptype);
		dsn[strlen(dsn)] = '('; /* THIS WON'T WORK: strncat(dsn, "(", 1); */
		strcat(dsn, ")");
	}
	if (len - DSN_LEN(el->dbsyntax) - DSN_LEN(el->phptype) > 0) {
		strcat(dsn, "://");
	}
	/* username */
	if (el->username != NULL) {
		strcat(dsn, el->username);
		/* password */
		if (el->password != NULL) {
			strcat(dsn, ":");
			strcat(dsn, el->password);
		}
	}
	/* protocol */
	if (el->protocol != NULL && ! strcmp(el->protocol, "tcp")) {
		if (0) { /* strict DSN case, part 1/2 */
			strcat(dsn, "tcp(");
		}
		/* hostspec */
		if (el->hostspec != NULL) {
			strcat(dsn, el->hostspec);
		}
		/* port */
		if (el->port != NULL && strcmp(el->port, "") && atoi(el->port) > 0) {
			strcat(dsn, ":");
			strcat(dsn, el->port);
		}
		if (0) { /* strict DSN case, part 2/2 */
			strcat(dsn, ")");
		}
	} else if (el->protocol != NULL && ! strcmp(el->protocol, "unix")) {
		strcat(dsn, "unix(");
		/* socket */
		if (el->socket != NULL) {
			strcat(dsn, el->socket);
		}
		strcat(dsn, ")");
	} else {
		/* hostspec */
		if (el->hostspec != NULL) {
			strcat(dsn, el->hostspec);
		}
	}
	/* database */
	if (el->database != NULL) {
		strcat(dsn, "/");
		strcat(dsn, el->database);
	}
	/* query */ /* TODO: query handling imrpovements */
	if (el->query != NULL) {
		strcat(dsn, "?");
		strcat(dsn, el->query);
	}

	return dsn; /* success */
} /* }}} */

#define DSN_TRIM(str, nptr, n)	do { back[n] = str[nptr - str]; str[nptr - str] = 0; } while (0)
#define DSN_RST(str, nptr, n)	(str[nptr - str] = back[n])

	int
dsn_parse(input_dsn, el)
	const char *input_dsn;
	struct dsn_elements *el;
{ /* {{{ */
	char back[8];
	char *dsn = strdup(input_dsn);
	char *c;
	char *tmp = NULL, *tmp2 = NULL;
	char *phptype    = NULL;
	char *dbsyntax   = NULL;
	char *username   = NULL;
	char *password   = NULL;
	char *protocol   = NULL;
	char *proto_opts = NULL;
	char *hostspec   = NULL;
	char *port       = NULL;
	char *socket     = NULL;
	char *database   = NULL;
	char *query      = NULL;

	if (dsn == NULL)
		goto ERR;

	if ((c = strstr(dsn, "://")) != NULL) {
		DSN_TRIM(dsn, c, 0);
		phptype = urldecode(dsn);
		DSN_RST(dsn, c, 0);
	} else {
		phptype = urldecode(dsn);
		c = 0;
	}

	if (phptype == NULL)
		goto ERR;

	if ((tmp = strchr(phptype, '(')) != NULL) {
		DSN_TRIM(phptype, tmp, 0);
		tmp++;
		if ((tmp2 = strchr(tmp, ')')) != NULL) {
			DSN_TRIM(tmp, tmp2, 0);
		} else {
			goto ERR;
		}
		dbsyntax = urldecode(tmp);
	} else {
		dbsyntax = strdup(phptype);
	}

	if (dbsyntax == NULL)
		goto ERR;

	if (c) {
		c += 3;
		/* printf ("c: %s\n", c); */
		if ((tmp = strrchr(c, '@')) != NULL) {
			DSN_TRIM(c, tmp, 0);
			/* printf ("c: %s\n", c); */
			username = urldecode(c);
			if (username == NULL)
				goto ERR;
			DSN_RST(c, tmp, 0);
			c = tmp + 1;
			if ((tmp2 = strchr(username, ':')) != NULL) { /* maybe strrchr? */
				DSN_TRIM(username, tmp2, 0);
				password = urldecode(tmp2 + 1);
				if (password == NULL)
					goto ERR;
			}
		}

		if ((tmp = strchr(c, '(')) && (tmp != c) && (tmp2 = strchr(c, ')')) && (tmp2 > tmp)) {
			DSN_TRIM(c, tmp, 0);
			DSN_TRIM(c, tmp2, 1);
			protocol = urldecode(c);
			if (protocol == NULL)
				goto ERR;
			proto_opts = urldecode(tmp + 1);
			/* printf ("proto_opts: %s\n", proto_opts); */
			c = strchr(tmp2 + 1, '/');
			if (c == NULL)
				goto ERR;
			c++;
			DSN_RST(c, tmp2, 1);
			DSN_RST(c, tmp, 0);
		} else { /* old format */
			if ((tmp = strchr(c, '+')) != NULL) {
				DSN_TRIM(c, tmp, 0);
				protocol = urldecode(c);
				if (protocol == NULL)
					goto ERR;
				c = tmp + 1;
			}
			if ((tmp = strchr(c, '/')) != NULL) {
				DSN_TRIM(c, tmp, 0);
				proto_opts = urldecode(c);
				if (proto_opts == NULL)
					goto ERR;
				/* printf ("proto_opts: %s\n", proto_opts); */
				c = tmp + 1;
			} else {
				proto_opts = urldecode(c);
				if (proto_opts == NULL)
					goto ERR;
				c = 0;
			}
		}

		if (protocol && ! strlen(protocol)) {
			free(protocol);
			protocol = NULL;
		}
		if (protocol == NULL)
			protocol = strdup("tcp");
		if (protocol == NULL)
			goto ERR;
	}

	if (proto_opts) {
		/*tmp = urldecode(proto_opts);
		if (! tmp) goto ERR;
		free(proto_opts);
		proto_opts = tmp;*/
		if (! strcmp(protocol, "tcp")) {
			if ((tmp = strchr(proto_opts, ':')) != NULL) {
				DSN_TRIM(proto_opts, tmp, 0);
				hostspec = strdup(proto_opts);
				if (hostspec == NULL)
					goto ERR;
				port = strdup(tmp + 1);
				if (port == NULL)
					goto ERR;
				free(proto_opts);
				proto_opts = 0;
			} else {
				hostspec = proto_opts;
				proto_opts = 0;
			}
		} else if (! strcmp(protocol, "unix")) {
			socket = proto_opts;
			proto_opts = 0;
		} else {
			free(proto_opts);
			proto_opts = 0;
		}
	}

	if (c && strlen(c)) { /* path + query string */
		if ((tmp = strchr(c, '?')) != NULL) {
			DSN_TRIM(c, tmp, 0);
			database = strdup(c);
			if (database == NULL)
				goto ERR;
			query = strdup(tmp + 1);
			if (query == NULL)
				goto ERR;
			c = 0;
		} else {
			database = strdup(c);
			if (database == NULL)
				goto ERR;
			c = 0;
		}
	} else if (c) {
		c = 0;
	}

	dsn_free_ptr(&dsn);

	/* XXX it might be better to `el -> X = mystrdup(X); sfree(X);'
	   where mystrdup returns NULL if X == NULL */
	el->phptype  = phptype;
	el->dbsyntax = dbsyntax;
	el->username = username;
	el->password = password;
	el->protocol = protocol;
	el->hostspec = hostspec;
	el->port     = port;
	el->socket   = socket;
	el->database = database;
	el->query    = query;
	return 1; /* success */

ERR:
	dsn_free_ptr(&dsn);
	dsn_free_ptr(&phptype);
	dsn_free_ptr(&dbsyntax);
	dsn_free_ptr(&username);
	dsn_free_ptr(&password);
	dsn_free_ptr(&protocol);
	dsn_free_ptr(&hostspec);
	dsn_free_ptr(&port);
	dsn_free_ptr(&socket);
	dsn_free_ptr(&database);
	return 0; /* memory allocation failure */
} /* }}} */

#if defined(SELF) || defined(SELFTEST) || defined(SELF_DSN) /* {{{ */

#include <stdio.h>

int test(const char *dsn)
{
	register char *dsn2;
	struct dsn_elements e;
	if (! dsn_parse(dsn, &e)) {
		printf("Memory allocation error when parsing DSN string.\n");
		return 0; /* failure */
	}

	if ((dsn2 = dsn_glue(&e)) == NULL) {
		printf("Memory allocation error when compiling DSN string.\n");
		return 0;
	}

	if (strcmp(dsn, dsn2)) {
		printf("DSN strings do not match.\n");
		printf("  original DSN: %s\n", dsn);
		printf("  compiled DSN: %s\n", dsn2);
	}
	free(dsn2);

	printf ("DSN: %s\nArray\n(\n", dsn);
	printf ("    [phptype] => %s\n",  e.phptype  ? e.phptype  : "");
	printf ("    [dbsyntax] => %s\n", e.dbsyntax ? e.dbsyntax : "");
	printf ("    [username] => %s\n", e.username ? e.username : "");
	printf ("    [password] => %s\n", e.password ? e.password : "");
	printf ("    [protocol] => %s\n", e.protocol ? e.protocol : "");
	printf ("    [hostspec] => %s\n", e.hostspec ? e.hostspec : "");
	printf ("    [port] => %s\n",     e.port     ? e.port     : "");
	printf ("    [socket] => %s\n",   e.socket   ? e.socket   : "");
	printf ("    [database] => %s\n", e.database ? e.database : "");
	if (e.query != NULL) {
		printf ("    [query] => %s\n", e.query);
	}
	printf (")\n");
	dsn_free(&e);
	return 1; /* success */
}

int main(void)
{
	/* borrowed from db_parsedsn.phpt */
	test("mysql");
	test("odbc(mssql)");
	test("mysql://localhost");
	test("mysql://remote.host.com/db");
	test("oci8://system:manager@");
	test("oci8://user:pass@tns-name");
	test("odbc(solid)://foo:bar@tcp+localhost+1313");  /* deprecated */
	test("pgsql://user@unix+localhost/pear");          /* deprecated */
	test("ibase://user%40domain:password@host");
	test("ibase://user@domain:pass@word@/database");   /* also supported */
	test("ifx://user@domain:pass@word@host.com//usr/db/general.db");
	test("ifx://remote.host.com/c:\\windows\\my.db");
	test("oci8://SHOOTOUT:******@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.101.161)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME=TIS)))");
	test("odbc(solid)://foo:bar@localhost:1313");

	/* new formats */
	test("pgsql://user@unix()/pear");
	test("mysql://user@unix(/path/to/socket)/pear");
	test("pgsql://user@tcp()/pear");
	test("pgsql://user@tcp(somehost)/pear");
	test("pgsql://user:pass@word@tcp(somehost:7777)/pear");

	/* special backend options */
	test("ibase://user:pass@localhost//var/lib/dbase.dbf?role=foo");
	test("dbase://@/?role=foo&dialect=bar");

	return 0;
}

#endif /* #if defined(SELF) || defined(SELFTEST) || defined(SELF_DSN) */ /* }}} */

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