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authorJunio C Hamano <junkio@cox.net>2006-09-28 06:56:55 (GMT)
committerJunio C Hamano <junkio@cox.net>2006-09-28 06:56:55 (GMT)
commit2d5b459107cf07bbb307cfb196c2007c497a6dd2 (patch)
treeb7f398e90acf62af13709dba1739db30144913ee
parent51b2dd4e3f730f6be6c19faf3b4a04caea9e0420 (diff)
parenteb30aed7c69190fd648947d54bbb9ebe53c67715 (diff)
downloadgit-2d5b459107cf07bbb307cfb196c2007c497a6dd2.zip
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Merge branch 'jl/virtual'
* jl/virtual: Removed memory leaks from interpolation table uses. Cleaned up git-daemon virtual hosting support.
-rw-r--r--Documentation/git-daemon.txt43
-rw-r--r--Makefile3
-rw-r--r--compat/inet_pton.c220
-rw-r--r--daemon.c175
-rw-r--r--interpolate.c26
-rw-r--r--interpolate.h3
6 files changed, 436 insertions, 34 deletions
diff --git a/Documentation/git-daemon.txt b/Documentation/git-daemon.txt
index 51d7c94..d562232 100644
--- a/Documentation/git-daemon.txt
+++ b/Documentation/git-daemon.txt
@@ -8,14 +8,15 @@ git-daemon - A really simple server for git repositories
SYNOPSIS
--------
[verse]
-'git-daemon' [--verbose] [--syslog] [--inetd | --port=n] [--export-all]
+'git-daemon' [--verbose] [--syslog] [--export-all]
[--timeout=n] [--init-timeout=n] [--strict-paths]
[--base-path=path] [--user-path | --user-path=path]
[--interpolated-path=pathtemplate]
+ [--reuseaddr] [--detach] [--pid-file=file]
[--enable=service] [--disable=service]
[--allow-override=service] [--forbid-override=service]
- [--reuseaddr] [--detach] [--pid-file=file]
- [--user=user [--group=group]] [directory...]
+ [--inetd | [--listen=host_or_ipaddr] [--port=n] [--user=user [--group=group]]
+ [directory...]
DESCRIPTION
-----------
@@ -54,8 +55,12 @@ OPTIONS
--interpolated-path=pathtemplate::
To support virtual hosting, an interpolated path template can be
used to dynamically construct alternate paths. The template
- supports %H for the target hostname as supplied by the client,
+ supports %H for the target hostname as supplied by the client but
+ converted to all lowercase, %CH for the canonical hostname,
+ %IP for the server's IP address, %P for the port number,
and %D for the absolute path of the named repository.
+ After interpolation, the path is validated against the directory
+ whitelist.
--export-all::
Allow pulling from all directories that look like GIT repositories
@@ -64,9 +69,17 @@ OPTIONS
--inetd::
Have the server run as an inetd service. Implies --syslog.
+ Incompatible with --port, --listen, --user and --group options.
+
+--listen=host_or_ipaddr::
+ Listen on an a specific IP address or hostname. IP addresses can
+ be either an IPv4 address or an IPV6 address if supported. If IPv6
+ is not supported, then --listen=hostname is also not supported and
+ --listen must be given an IPv4 address.
+ Incompatible with '--inetd' option.
---port::
- Listen on an alternative port.
+--port=n::
+ Listen on an alternative port. Incompatible with '--inetd' option.
--init-timeout::
Timeout between the moment the connection is established and the
@@ -182,6 +195,24 @@ clients, a symlink from `/software` into the appropriate
default repository could be made as well.
+git-daemon as regular daemon for virtual hosts::
+ To set up `git-daemon` as a regular, non-inetd service that
+ handles repositories for multiple virtual hosts based on
+ their IP addresses, start the daemon like this:
++
+------------------------------------------------
+ git-daemon --verbose --export-all
+ --interpolated-path=/pub/%IP/%D
+ /pub/192.168.1.200/software
+ /pub/10.10.220.23/software
+------------------------------------------------
++
+In this example, the root-level directory `/pub` will contain
+a subdirectory for each virtual host IP address supported.
+Repositories can still be accessed by hostname though, assuming
+they correspond to these IP addresses.
+
+
Author
------
Written by Linus Torvalds <torvalds@osdl.org>, YOSHIFUJI Hideaki
diff --git a/Makefile b/Makefile
index c888c81..e649d72 100644
--- a/Makefile
+++ b/Makefile
@@ -522,6 +522,9 @@ endif
ifdef NO_INET_NTOP
LIB_OBJS += compat/inet_ntop.o
endif
+ifdef NO_INET_PTON
+ LIB_OBJS += compat/inet_pton.o
+endif
ifdef NO_ICONV
ALL_CFLAGS += -DNO_ICONV
diff --git a/compat/inet_pton.c b/compat/inet_pton.c
new file mode 100644
index 0000000..5704e0d
--- /dev/null
+++ b/compat/inet_pton.c
@@ -0,0 +1,220 @@
+/*
+ * Copyright (C) 1996-2001 Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
+ * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+ * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
+ * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
+ * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <string.h>
+
+#ifndef NS_INT16SZ
+#define NS_INT16SZ 2
+#endif
+
+#ifndef NS_INADDRSZ
+#define NS_INADDRSZ 4
+#endif
+
+#ifndef NS_IN6ADDRSZ
+#define NS_IN6ADDRSZ 16
+#endif
+
+/*
+ * WARNING: Don't even consider trying to compile this on a system where
+ * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
+ */
+
+static int inet_pton4(const char *src, unsigned char *dst);
+static int inet_pton6(const char *src, unsigned char *dst);
+
+/* int
+ * inet_pton4(src, dst)
+ * like inet_aton() but without all the hexadecimal and shorthand.
+ * return:
+ * 1 if `src' is a valid dotted quad, else 0.
+ * notice:
+ * does not touch `dst' unless it's returning 1.
+ * author:
+ * Paul Vixie, 1996.
+ */
+static int
+inet_pton4(const char *src, unsigned char *dst)
+{
+ static const char digits[] = "0123456789";
+ int saw_digit, octets, ch;
+ unsigned char tmp[NS_INADDRSZ], *tp;
+
+ saw_digit = 0;
+ octets = 0;
+ *(tp = tmp) = 0;
+ while ((ch = *src++) != '\0') {
+ const char *pch;
+
+ if ((pch = strchr(digits, ch)) != NULL) {
+ unsigned int new = *tp * 10 + (pch - digits);
+
+ if (new > 255)
+ return (0);
+ *tp = new;
+ if (! saw_digit) {
+ if (++octets > 4)
+ return (0);
+ saw_digit = 1;
+ }
+ } else if (ch == '.' && saw_digit) {
+ if (octets == 4)
+ return (0);
+ *++tp = 0;
+ saw_digit = 0;
+ } else
+ return (0);
+ }
+ if (octets < 4)
+ return (0);
+ memcpy(dst, tmp, NS_INADDRSZ);
+ return (1);
+}
+
+/* int
+ * inet_pton6(src, dst)
+ * convert presentation level address to network order binary form.
+ * return:
+ * 1 if `src' is a valid [RFC1884 2.2] address, else 0.
+ * notice:
+ * (1) does not touch `dst' unless it's returning 1.
+ * (2) :: in a full address is silently ignored.
+ * credit:
+ * inspired by Mark Andrews.
+ * author:
+ * Paul Vixie, 1996.
+ */
+
+#ifndef NO_IPV6
+static int
+inet_pton6(const char *src, unsigned char *dst)
+{
+ static const char xdigits_l[] = "0123456789abcdef",
+ xdigits_u[] = "0123456789ABCDEF";
+ unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
+ const char *xdigits, *curtok;
+ int ch, saw_xdigit;
+ unsigned int val;
+
+ memset((tp = tmp), '\0', NS_IN6ADDRSZ);
+ endp = tp + NS_IN6ADDRSZ;
+ colonp = NULL;
+ /* Leading :: requires some special handling. */
+ if (*src == ':')
+ if (*++src != ':')
+ return (0);
+ curtok = src;
+ saw_xdigit = 0;
+ val = 0;
+ while ((ch = *src++) != '\0') {
+ const char *pch;
+
+ if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
+ pch = strchr((xdigits = xdigits_u), ch);
+ if (pch != NULL) {
+ val <<= 4;
+ val |= (pch - xdigits);
+ if (val > 0xffff)
+ return (0);
+ saw_xdigit = 1;
+ continue;
+ }
+ if (ch == ':') {
+ curtok = src;
+ if (!saw_xdigit) {
+ if (colonp)
+ return (0);
+ colonp = tp;
+ continue;
+ }
+ if (tp + NS_INT16SZ > endp)
+ return (0);
+ *tp++ = (unsigned char) (val >> 8) & 0xff;
+ *tp++ = (unsigned char) val & 0xff;
+ saw_xdigit = 0;
+ val = 0;
+ continue;
+ }
+ if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
+ inet_pton4(curtok, tp) > 0) {
+ tp += NS_INADDRSZ;
+ saw_xdigit = 0;
+ break; /* '\0' was seen by inet_pton4(). */
+ }
+ return (0);
+ }
+ if (saw_xdigit) {
+ if (tp + NS_INT16SZ > endp)
+ return (0);
+ *tp++ = (unsigned char) (val >> 8) & 0xff;
+ *tp++ = (unsigned char) val & 0xff;
+ }
+ if (colonp != NULL) {
+ /*
+ * Since some memmove()'s erroneously fail to handle
+ * overlapping regions, we'll do the shift by hand.
+ */
+ const int n = tp - colonp;
+ int i;
+
+ for (i = 1; i <= n; i++) {
+ endp[- i] = colonp[n - i];
+ colonp[n - i] = 0;
+ }
+ tp = endp;
+ }
+ if (tp != endp)
+ return (0);
+ memcpy(dst, tmp, NS_IN6ADDRSZ);
+ return (1);
+}
+#endif
+
+/* int
+ * isc_net_pton(af, src, dst)
+ * convert from presentation format (which usually means ASCII printable)
+ * to network format (which is usually some kind of binary format).
+ * return:
+ * 1 if the address was valid for the specified address family
+ * 0 if the address wasn't valid (`dst' is untouched in this case)
+ * -1 if some other error occurred (`dst' is untouched in this case, too)
+ * author:
+ * Paul Vixie, 1996.
+ */
+int
+inet_pton(int af, const char *src, void *dst)
+{
+ switch (af) {
+ case AF_INET:
+ return (inet_pton4(src, dst));
+#ifndef NO_IPV6
+ case AF_INET6:
+ return (inet_pton6(src, dst));
+#endif
+ default:
+ errno = EAFNOSUPPORT;
+ return (-1);
+ }
+ /* NOTREACHED */
+}
diff --git a/daemon.c b/daemon.c
index eb4f3f1..5335d21 100644
--- a/daemon.c
+++ b/daemon.c
@@ -9,6 +9,7 @@
#include <syslog.h>
#include <pwd.h>
#include <grp.h>
+#include <limits.h>
#include "pkt-line.h"
#include "cache.h"
#include "exec_cmd.h"
@@ -19,13 +20,15 @@ static int verbose;
static int reuseaddr;
static const char daemon_usage[] =
-"git-daemon [--verbose] [--syslog] [--inetd | --port=n] [--export-all]\n"
+"git-daemon [--verbose] [--syslog] [--export-all]\n"
" [--timeout=n] [--init-timeout=n] [--strict-paths]\n"
" [--base-path=path] [--user-path | --user-path=path]\n"
" [--interpolated-path=path]\n"
" [--reuseaddr] [--detach] [--pid-file=file]\n"
" [--[enable|disable|allow-override|forbid-override]=service]\n"
-" [--user=user [[--group=group]] [directory...]";
+" [--inetd | [--listen=host_or_ipaddr] [--port=n]\n"
+" [--user=user [--group=group]]\n"
+" [directory...]";
/* List of acceptable pathname prefixes */
static char **ok_paths;
@@ -56,13 +59,19 @@ static unsigned int init_timeout;
* Feel free to make dynamic as needed.
*/
#define INTERP_SLOT_HOST (0)
-#define INTERP_SLOT_DIR (1)
-#define INTERP_SLOT_PERCENT (2)
+#define INTERP_SLOT_CANON_HOST (1)
+#define INTERP_SLOT_IP (2)
+#define INTERP_SLOT_PORT (3)
+#define INTERP_SLOT_DIR (4)
+#define INTERP_SLOT_PERCENT (5)
static struct interp interp_table[] = {
{ "%H", 0},
+ { "%CH", 0},
+ { "%IP", 0},
+ { "%P", 0},
{ "%D", 0},
- { "%%", "%"},
+ { "%%", 0},
};
@@ -396,7 +405,11 @@ static void make_service_overridable(const char *name, int ena) {
die("No such service %s", name);
}
-static void parse_extra_args(char *extra_args, int buflen)
+/*
+ * Separate the "extra args" information as supplied by the client connection.
+ * Any resulting data is squirrelled away in the given interpolation table.
+ */
+static void parse_extra_args(struct interp *table, char *extra_args, int buflen)
{
char *val;
int vallen;
@@ -408,16 +421,88 @@ static void parse_extra_args(char *extra_args, int buflen)
val = extra_args + 5;
vallen = strlen(val) + 1;
if (*val) {
- char *save = xmalloc(vallen);
- interp_table[INTERP_SLOT_HOST].value = save;
- strlcpy(save, val, vallen);
+ /* Split <host>:<port> at colon. */
+ char *host = val;
+ char *port = strrchr(host, ':');
+ if (port) {
+ *port = 0;
+ port++;
+ interp_set_entry(table, INTERP_SLOT_PORT, port);
+ }
+ interp_set_entry(table, INTERP_SLOT_HOST, host);
}
+
/* On to the next one */
extra_args = val + vallen;
}
}
}
+void fill_in_extra_table_entries(struct interp *itable)
+{
+ char *hp;
+
+ /*
+ * Replace literal host with lowercase-ized hostname.
+ */
+ hp = interp_table[INTERP_SLOT_HOST].value;
+ for ( ; *hp; hp++)
+ *hp = tolower(*hp);
+
+ /*
+ * Locate canonical hostname and its IP address.
+ */
+#ifndef NO_IPV6
+ {
+ struct addrinfo hints;
+ struct addrinfo *ai, *ai0;
+ int gai;
+ static char addrbuf[HOST_NAME_MAX + 1];
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_flags = AI_CANONNAME;
+
+ gai = getaddrinfo(interp_table[INTERP_SLOT_HOST].value, 0, &hints, &ai0);
+ if (!gai) {
+ for (ai = ai0; ai; ai = ai->ai_next) {
+ struct sockaddr_in *sin_addr = (void *)ai->ai_addr;
+
+ inet_ntop(AF_INET, &sin_addr->sin_addr,
+ addrbuf, sizeof(addrbuf));
+ interp_set_entry(interp_table,
+ INTERP_SLOT_CANON_HOST, ai->ai_canonname);
+ interp_set_entry(interp_table,
+ INTERP_SLOT_IP, addrbuf);
+ break;
+ }
+ freeaddrinfo(ai0);
+ }
+ }
+#else
+ {
+ struct hostent *hent;
+ struct sockaddr_in sa;
+ char **ap;
+ static char addrbuf[HOST_NAME_MAX + 1];
+
+ hent = gethostbyname(interp_table[INTERP_SLOT_HOST].value);
+
+ ap = hent->h_addr_list;
+ memset(&sa, 0, sizeof sa);
+ sa.sin_family = hent->h_addrtype;
+ sa.sin_port = htons(0);
+ memcpy(&sa.sin_addr, *ap, hent->h_length);
+
+ inet_ntop(hent->h_addrtype, &sa.sin_addr,
+ addrbuf, sizeof(addrbuf));
+
+ interp_set_entry(interp_table, INTERP_SLOT_CANON_HOST, hent->h_name);
+ interp_set_entry(interp_table, INTERP_SLOT_IP, addrbuf);
+ }
+#endif
+}
+
+
static int execute(struct sockaddr *addr)
{
static char line[1000];
@@ -458,8 +543,16 @@ static int execute(struct sockaddr *addr)
if (len && line[len-1] == '\n')
line[--len] = 0;
- if (len != pktlen)
- parse_extra_args(line + len + 1, pktlen - len - 1);
+ /*
+ * Initialize the path interpolation table for this connection.
+ */
+ interp_clear_table(interp_table, ARRAY_SIZE(interp_table));
+ interp_set_entry(interp_table, INTERP_SLOT_PERCENT, "%");
+
+ if (len != pktlen) {
+ parse_extra_args(interp_table, line + len + 1, pktlen - len - 1);
+ fill_in_extra_table_entries(interp_table);
+ }
for (i = 0; i < ARRAY_SIZE(daemon_service); i++) {
struct daemon_service *s = &(daemon_service[i]);
@@ -467,7 +560,12 @@ static int execute(struct sockaddr *addr)
if (!strncmp("git-", line, 4) &&
!strncmp(s->name, line + 4, namelen) &&
line[namelen + 4] == ' ') {
- interp_table[INTERP_SLOT_DIR].value = line+namelen+5;
+ /*
+ * Note: The directory here is probably context sensitive,
+ * and might depend on the actual service being performed.
+ */
+ interp_set_entry(interp_table,
+ INTERP_SLOT_DIR, line + namelen + 5);
return run_service(interp_table, s);
}
}
@@ -663,23 +761,22 @@ static int set_reuse_addr(int sockfd)
#ifndef NO_IPV6
-static int socksetup(int port, int **socklist_p)
+static int socksetup(char *listen_addr, int listen_port, int **socklist_p)
{
int socknum = 0, *socklist = NULL;
int maxfd = -1;
char pbuf[NI_MAXSERV];
-
struct addrinfo hints, *ai0, *ai;
int gai;
- sprintf(pbuf, "%d", port);
+ sprintf(pbuf, "%d", listen_port);
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
hints.ai_flags = AI_PASSIVE;
- gai = getaddrinfo(NULL, pbuf, &hints, &ai0);
+ gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0);
if (gai)
die("getaddrinfo() failed: %s\n", gai_strerror(gai));
@@ -733,20 +830,27 @@ static int socksetup(int port, int **socklist_p)
#else /* NO_IPV6 */
-static int socksetup(int port, int **socklist_p)
+static int socksetup(char *lisen_addr, int listen_port, int **socklist_p)
{
struct sockaddr_in sin;
int sockfd;
+ memset(&sin, 0, sizeof sin);
+ sin.sin_family = AF_INET;
+ sin.sin_port = htons(listen_port);
+
+ if (listen_addr) {
+ /* Well, host better be an IP address here. */
+ if (inet_pton(AF_INET, listen_addr, &sin.sin_addr.s_addr) <= 0)
+ return 0;
+ } else {
+ sin.sin_addr.s_addr = htonl(INADDR_ANY);
+ }
+
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
return 0;
- memset(&sin, 0, sizeof sin);
- sin.sin_family = AF_INET;
- sin.sin_addr.s_addr = htonl(INADDR_ANY);
- sin.sin_port = htons(port);
-
if (set_reuse_addr(sockfd)) {
close(sockfd);
return 0;
@@ -855,13 +959,14 @@ static void store_pid(const char *path)
fclose(f);
}
-static int serve(int port, struct passwd *pass, gid_t gid)
+static int serve(char *listen_addr, int listen_port, struct passwd *pass, gid_t gid)
{
int socknum, *socklist;
- socknum = socksetup(port, &socklist);
+ socknum = socksetup(listen_addr, listen_port, &socklist);
if (socknum == 0)
- die("unable to allocate any listen sockets on port %u", port);
+ die("unable to allocate any listen sockets on host %s port %u",
+ listen_addr, listen_port);
if (pass && gid &&
(initgroups(pass->pw_name, gid) || setgid (gid) ||
@@ -873,7 +978,8 @@ static int serve(int port, struct passwd *pass, gid_t gid)
int main(int argc, char **argv)
{
- int port = DEFAULT_GIT_PORT;
+ int listen_port = 0;
+ char *listen_addr = NULL;
int inetd_mode = 0;
const char *pid_file = NULL, *user_name = NULL, *group_name = NULL;
int detach = 0;
@@ -890,12 +996,20 @@ int main(int argc, char **argv)
for (i = 1; i < argc; i++) {
char *arg = argv[i];
+ if (!strncmp(arg, "--listen=", 9)) {
+ char *p = arg + 9;
+ char *ph = listen_addr = xmalloc(strlen(arg + 9) + 1);
+ while (*p)
+ *ph++ = tolower(*p++);
+ *ph = 0;
+ continue;
+ }
if (!strncmp(arg, "--port=", 7)) {
char *end;
unsigned long n;
n = strtoul(arg+7, &end, 0);
if (arg[7] && !*end) {
- port = n;
+ listen_port = n;
continue;
}
}
@@ -995,6 +1109,11 @@ int main(int argc, char **argv)
if (inetd_mode && (group_name || user_name))
die("--user and --group are incompatible with --inetd");
+ if (inetd_mode && (listen_port || listen_addr))
+ die("--listen= and --port= are incompatible with --inetd");
+ else if (listen_port == 0)
+ listen_port = DEFAULT_GIT_PORT;
+
if (group_name && !user_name)
die("--group supplied without --user");
@@ -1043,5 +1162,5 @@ int main(int argc, char **argv)
if (pid_file)
store_pid(pid_file);
- return serve(port, pass, gid);
+ return serve(listen_addr, listen_port, pass, gid);
}
diff --git a/interpolate.c b/interpolate.c
index 4570c12..62701d8 100644
--- a/interpolate.c
+++ b/interpolate.c
@@ -4,9 +4,35 @@
#include <string.h>
+#include "git-compat-util.h"
#include "interpolate.h"
+void interp_set_entry(struct interp *table, int slot, char *value)
+{
+ char *oldval = table[slot].value;
+ char *newval = value;
+
+ if (oldval)
+ free(oldval);
+
+ if (value)
+ newval = xstrdup(value);
+
+ table[slot].value = newval;
+}
+
+
+void interp_clear_table(struct interp *table, int ninterps)
+{
+ int i;
+
+ for (i = 0; i < ninterps; i++) {
+ interp_set_entry(table, i, NULL);
+ }
+}
+
+
/*
* Convert a NUL-terminated string in buffer orig
* into the supplied buffer, result, whose length is reslen,
diff --git a/interpolate.h b/interpolate.h
index d16f924..a55fb8e 100644
--- a/interpolate.h
+++ b/interpolate.h
@@ -16,6 +16,9 @@ struct interp {
char *value;
};
+extern void interp_set_entry(struct interp *table, int slot, char *value);
+extern void interp_clear_table(struct interp *table, int ninterps);
+
extern int interpolate(char *result, int reslen,
const char *orig,
const struct interp *interps, int ninterps);