X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=src%2Fhttp.c;h=e697b4e58b23c4ab33aeda047f72f6eddd42b926;hb=5a145dc87e4756afc3e247cded32a9666457f065;hp=09d9f5c8105dad42d7727484820a372b7c84c5fe;hpb=41b3d6e76417912fda803543325e1edba21896ba;p=pazpar2-moved-to-github.git

diff --git a/src/http.c b/src/http.c
index 09d9f5c..e697b4e 100644
--- a/src/http.c
+++ b/src/http.c
@@ -1,11 +1,27 @@
-/*
- * $Id: http.c,v 1.6 2007-01-08 12:43:41 adam Exp $
- */
+/* This file is part of Pazpar2.
+   Copyright (C) 2006-2008 Index Data
+
+Pazpar2 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 2, or (at your option) any later
+version.
+
+Pazpar2 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, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
 
 #include <stdio.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <sys/uio.h>
+#include <yaz/snprintf.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <strings.h>
@@ -14,14 +30,19 @@
 #include <netdb.h>
 #include <errno.h>
 #include <assert.h>
+#include <string.h>
 
 #if HAVE_CONFIG_H
 #include <cconfig.h>
 #endif
 
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+
 #include <yaz/yaz-util.h>
 #include <yaz/comstack.h>
-#include <netdb.h>
+#include <yaz/nmem.h>
 
 #include "util.h"
 #include "eventl.h"
@@ -29,17 +50,37 @@
 #include "http.h"
 #include "http_command.h"
 
+#define MAX_HTTP_HEADER 4096
+
 static void proxy_io(IOCHAN i, int event);
-static struct http_channel *http_create(void);
+static struct http_channel *http_create(const char *addr);
 static void http_destroy(IOCHAN i);
 
-extern IOCHAN channel_list;
-
-static struct sockaddr_in *proxy_addr = 0; // If this is set, we proxy normal HTTP requests
+// If this is set, we proxy normal HTTP requests
+static struct sockaddr_in *proxy_addr = 0; 
 static char proxy_url[256] = "";
+static char myurl[256] = "";
 static struct http_buf *http_buf_freelist = 0;
 static struct http_channel *http_channel_freelist = 0;
 
+struct http_channel_observer_s {
+    void *data;
+    void *data2;
+    http_channel_destroy_t destroy;
+    struct http_channel_observer_s *next;
+    struct http_channel *chan;
+};
+
+
+static const char *http_lookup_header(struct http_header *header,
+                                      const char *name)
+{
+    for (; header; header = header->next)
+        if (!strcasecmp(name, header->name))
+            return header->value;
+    return 0;
+}
+
 static struct http_buf *http_buf_create()
 {
     struct http_buf *r;
@@ -74,17 +115,6 @@ static void http_buf_destroy_queue(struct http_buf *b)
     }
 }
 
-#ifdef GAGA
-// Calculate length of chain
-static int http_buf_len(struct http_buf *b)
-{
-    int sum = 0;
-    for (; b; b = b->next)
-        sum += b->len;
-    return sum;
-}
-#endif
-
 static struct http_buf *http_buf_bybuf(char *b, int len)
 {
     struct http_buf *res = 0;
@@ -92,10 +122,10 @@ static struct http_buf *http_buf_bybuf(char *b, int len)
 
     while (len)
     {
-        *p = http_buf_create();
         int tocopy = len;
         if (tocopy > HTTP_BUF_SIZE)
             tocopy = HTTP_BUF_SIZE;
+        *p = http_buf_create();
         memcpy((*p)->buf, b, tocopy);
         (*p)->len = tocopy;
         len -= tocopy;
@@ -121,7 +151,7 @@ static struct http_buf *http_buf_bywrbuf(WRBUF wrbuf)
 
 // Non-destructively collapse chain of buffers into a string (max *len)
 // Return
-static int http_buf_peek(struct http_buf *b, char *buf, int len)
+static void http_buf_peek(struct http_buf *b, char *buf, int len)
 {
     int rd = 0;
     while (b && rd < len)
@@ -134,7 +164,14 @@ static int http_buf_peek(struct http_buf *b, char *buf, int len)
         b = b->next;
     }
     buf[rd] = '\0';
-    return rd;
+}
+
+static int http_buf_size(struct http_buf *b)
+{
+    int sz = 0;
+    for (; b; b = b->next)
+        sz += b->len;
+    return sz;
 }
 
 // Ddestructively munch up to len  from head of queue.
@@ -165,7 +202,8 @@ static int http_buf_read(struct http_buf **b, char *buf, int len)
     return rd;
 }
 
-void static urldecode(char *i, char *o)
+// Buffers may overlap.
+static void urldecode(char *i, char *o)
 {
     while (*i)
     {
@@ -187,6 +225,23 @@ void static urldecode(char *i, char *o)
     *o = '\0';
 }
 
+// Warning: Buffers may not overlap
+void urlencode(const char *i, char *o)
+{
+    while (*i)
+    {
+        if (strchr(" /:", *i))
+        {
+            sprintf(o, "%%%.2X", (int) *i);
+            o += 3;
+        }
+        else
+            *(o++) = *i;
+        i++;
+    }
+    *o = '\0';
+}
+
 void http_addheader(struct http_response *r, const char *name, const char *value)
 {
     struct http_channel *c = r->channel;
@@ -208,12 +263,11 @@ char *http_argbyname(struct http_request *r, char *name)
     return 0;
 }
 
-char *http_headerbyname(struct http_request *r, char *name)
+char *http_headerbyname(struct http_header *h, char *name)
 {
-    struct http_header *p;
-    for (p = r->headers; p; p = p->next)
-        if (!strcmp(p->name, name))
-            return p->value;
+    for (; h; h = h->next)
+        if (!strcmp(h->name, name))
+            return h->value;
     return 0;
 }
 
@@ -225,51 +279,186 @@ struct http_response *http_create_response(struct http_channel *c)
     r->channel = c;
     r->headers = 0;
     r->payload = 0;
+    r->content_type = "text/xml";
     return r;
 }
 
-// Check if we have a complete request. Return 0 or length (including trailing newline)
-// FIXME: Does not deal gracefully with requests carrying payload
-// but this is kind of OK since we will reject anything other than an empty GET
-static int request_check(struct http_buf *queue)
+
+static const char *next_crlf(const char *cp, size_t *skipped)
 {
-    char tmp[4096];
+    const char *next_cp = strchr(cp, '\n');
+    if (next_cp)
+    {
+        if (next_cp > cp && next_cp[-1] == '\r')
+            *skipped = next_cp - cp - 1;
+        else
+            *skipped = next_cp - cp;
+        next_cp++;
+    }
+    return next_cp;
+}
+
+// Check if buf contains a package (minus payload)
+static int package_check(const char *buf, int sz)
+{
+    int content_len = 0;
     int len = 0;
-    char *buf = tmp;
 
-    http_buf_peek(queue, tmp, 4096);
-    while (*buf) // Check if we have a sequence of lines terminated by an empty line
+    while (*buf)
     {
-        char *b = strstr(buf, "\r\n");
+        size_t skipped = 0;
+        const char *b = next_crlf(buf, &skipped);
 
         if (!b)
+        {
+            // we did not find CRLF.. See if buffer is too large..
+            if (sz >= MAX_HTTP_HEADER-1)
+                return MAX_HTTP_HEADER-1; // yes. Return that (will fail later)
+            break;
+        }
+        len += (b - buf);
+        if (skipped == 0)
+        {
+            // CRLF CRLF , i.e. end of header
+            if (len + content_len <= sz)
+                return len + content_len;
+            break;
+        }
+        buf = b;
+        // following first skip of \r\n so that we don't consider Method
+        if (!strncasecmp(buf, "Content-Length:", 15))
+        {
+            const char *cp = buf+15;
+            while (*cp == ' ')
+                cp++;
+            content_len = 0;
+            while (*cp && isdigit(*cp))
+                content_len = content_len*10 + (*cp++ - '0');
+            if (content_len < 0) /* prevent negative offsets */
+                content_len = 0;
+        }
+    }
+    return 0;     // incomplete request
+}
+
+// Check if we have a request. Return 0 or length
+static int request_check(struct http_buf *queue)
+{
+    char tmp[MAX_HTTP_HEADER];
+
+    // only peek at the header..
+    http_buf_peek(queue, tmp, MAX_HTTP_HEADER-1);
+    // still we only return non-zero if the complete request is received..
+    return package_check(tmp, http_buf_size(queue));
+}
+
+struct http_response *http_parse_response_buf(struct http_channel *c, const char *buf, int len)
+{
+    char tmp[MAX_HTTP_HEADER];
+    struct http_response *r = http_create_response(c);
+    char *p, *p2;
+    struct http_header **hp = &r->headers;
+
+    if (len >= MAX_HTTP_HEADER)
+        return 0;
+    memcpy(tmp, buf, len);
+    for (p = tmp; *p && *p != ' '; p++) // Skip HTTP version
+        ;
+    p++;
+    // Response code
+    for (p2 = p; *p2 && *p2 != ' ' && p2 - p < 3; p2++)
+        r->code[p2 - p] = *p2;
+    if (!(p = strstr(tmp, "\r\n")))
+        return 0;
+    p += 2;
+    while (*p)
+    {
+        if (!(p2 = strstr(p, "\r\n")))
             return 0;
+        if (p == p2) // End of headers
+            break;
+        else
+        {
+            struct http_header *h = *hp = nmem_malloc(c->nmem, sizeof(*h));
+            char *value = strchr(p, ':');
+            if (!value)
+                return 0;
+            *(value++) = '\0';
+            h->name = nmem_strdup(c->nmem, p);
+            while (isspace(*value))
+                value++;
+            if (value >= p2)  // Empty header;
+            {
+                h->value = "";
+                p = p2 + 2;
+                continue;
+            }
+            *p2 = '\0';
+            h->value = nmem_strdup(c->nmem, value);
+            h->next = 0;
+            hp = &h->next;
+            p = p2 + 2;
+        }
+    }
+    return r;
+}
+
+static int http_parse_arguments(struct http_request *r, NMEM nmem,
+                                const char *args)
+{
+    const char *p2 = args;
 
-        len += (b - buf) + 2;
-        if (b == buf)
-            return len;
-        buf = b + 2;
+    while (*p2)
+    {
+        struct http_argument *a;
+        const char *equal = strchr(p2, '=');
+        const char *eoa = strchr(p2, '&');
+        if (!equal)
+        {
+            yaz_log(YLOG_WARN, "Expected '=' in argument");
+            return -1;
+        }
+        if (!eoa)
+            eoa = equal + strlen(equal); // last argument
+        else if (equal > eoa)
+        {
+            yaz_log(YLOG_WARN, "Missing '&' in argument");
+            return -1;
+        }
+        a = nmem_malloc(nmem, sizeof(struct http_argument));
+        a->name = nmem_strdupn(nmem, p2, equal - p2);
+        a->value = nmem_strdupn(nmem, equal+1, eoa - equal - 1);
+        urldecode(a->name, a->name);
+        urldecode(a->value, a->value);
+        a->next = r->arguments;
+        r->arguments = a;
+        p2 = eoa;
+        while (*p2 == '&')
+            p2++;
     }
     return 0;
 }
 
-struct http_request *http_parse_request(struct http_channel *c, struct http_buf **queue,
-        int len)
+struct http_request *http_parse_request(struct http_channel *c,
+                                        struct http_buf **queue,
+                                        int len)
 {
     struct http_request *r = nmem_malloc(c->nmem, sizeof(*r));
     char *p, *p2;
-    char tmp[4096];
-    char *buf = tmp;
+    char *start = nmem_malloc(c->nmem, len+1);
+    char *buf = start;
 
-    if (len > 4096)
-        return 0;
     if (http_buf_read(queue, buf, len) < len)
+    {
+        yaz_log(YLOG_WARN, "http_buf_read < len (%d)", len);
         return 0;
-
+    }
     r->search = "";
     r->channel = c;
     r->arguments = 0;
     r->headers = 0;
+    r->content_buf = 0;
+    r->content_len = 0;
     // Parse first line
     for (p = buf, p2 = r->method; *p && *p != ' ' && p - buf < 19; p++)
         *(p2++) = *p;
@@ -282,13 +471,13 @@ struct http_request *http_parse_request(struct http_channel *c, struct http_buf
 
     if (!(buf = strchr(buf, ' ')))
     {
-        yaz_log(YLOG_WARN, "Syntax error in request (1)");
+        yaz_log(YLOG_WARN, "Missing Request-URI in HTTP request");
         return 0;
     }
     buf++;
     if (!(p = strchr(buf, ' ')))
     {
-        yaz_log(YLOG_WARN, "Syntax error in request (2)");
+        yaz_log(YLOG_WARN, "HTTP Request-URI not terminated (too long?)");
         return 0;
     }
     *(p++) = '\0';
@@ -299,29 +488,7 @@ struct http_request *http_parse_request(struct http_channel *c, struct http_buf
     {
         r->search = nmem_strdup(c->nmem, p2);
         // Parse Arguments
-        while (*p2)
-        {
-            struct http_argument *a;
-            char *equal = strchr(p2, '=');
-            char *eoa = strchr(p2, '&');
-            if (!equal)
-            {
-                yaz_log(YLOG_WARN, "Expected '=' in argument");
-                return 0;
-            }
-            if (!eoa)
-                eoa = equal + strlen(equal); // last argument
-            else
-                *(eoa++) = '\0';
-            a = nmem_malloc(c->nmem, sizeof(struct http_argument));
-            *(equal++) = '\0';
-            a->name = nmem_strdup(c->nmem, p2);
-            urldecode(equal, equal);
-            a->value = nmem_strdup(c->nmem, equal);
-            a->next = r->arguments;
-            r->arguments = a;
-            p2 = eoa;
-        }
+        http_parse_arguments(r, c->nmem, p2);
     }
     buf = p;
 
@@ -329,12 +496,15 @@ struct http_request *http_parse_request(struct http_channel *c, struct http_buf
         strcpy(r->http_version, "1.0");
     else
     {
-        buf += 5;
-        if (!(p = strstr(buf, "\r\n")))
+        size_t skipped;
+        buf += 5; // strlen("HTTP/")
+
+        p = (char*) next_crlf(buf, &skipped);
+        if (!p || skipped < 3 || skipped > 5)
             return 0;
-        *(p++) = '\0';
-        p++;
-        strcpy(r->http_version, buf);
+
+        memcpy(r->http_version, buf, skipped);
+        r->http_version[skipped] = '\0';
         buf = p;
     }
     strcpy(c->version, r->http_version);
@@ -342,47 +512,101 @@ struct http_request *http_parse_request(struct http_channel *c, struct http_buf
     r->headers = 0;
     while (*buf)
     {
-        if (!(p = strstr(buf, "\r\n")))
+        size_t skipped;
+
+        p = (char *) next_crlf(buf, &skipped);
+        if (!p)
+        {
             return 0;
-        if (p == buf)
+        }
+        else if (skipped == 0)
+        {
+            buf = p;
             break;
+        }
         else
         {
+            char *cp;
+            char *n_v = nmem_malloc(c->nmem, skipped+1);
             struct http_header *h = nmem_malloc(c->nmem, sizeof(*h));
-            if (!(p2 = strchr(buf, ':')))
+
+            memcpy(n_v, buf, skipped);
+            n_v[skipped] = '\0';
+
+            if (!(cp = strchr(n_v, ':')))
                 return 0;
-            *(p2++) = '\0';
-            h->name = nmem_strdup(c->nmem, buf);
-            while (isspace(*p2))
-                p2++;
-            if (p2 >= p) // Empty header?
-            {
-                buf = p + 2;
-                continue;
-            }
-            *p = '\0';
-            h->value = nmem_strdup(c->nmem, p2);
+            h->name = nmem_strdupn(c->nmem, n_v, cp - n_v);
+            cp++;
+            while (isspace(*cp))
+                cp++;
+            h->value = nmem_strdup(c->nmem, cp);
             h->next = r->headers;
             r->headers = h;
-            buf = p + 2;
+            buf = p;
         }
     }
 
+    // determine if we do keep alive
+    if (!strcmp(c->version, "1.0"))
+    {
+        const char *v = http_lookup_header(r->headers, "Connection");
+        if (v && !strcmp(v, "Keep-Alive"))
+            c->keep_alive = 1;
+        else
+            c->keep_alive = 0;
+    }
+    else
+    {
+        const char *v = http_lookup_header(r->headers, "Connection");
+        if (v && !strcmp(v, "close"))
+            c->keep_alive = 0;
+        else
+            c->keep_alive = 1;
+    }
+    if (buf < start + len)
+    {
+        const char *content_type = http_lookup_header(r->headers,
+                                                      "Content-Type");
+        r->content_len = start + len - buf;
+        r->content_buf = buf;
+
+        if (!strcmp(content_type, "application/x-www-form-urlencoded"))
+        {
+            http_parse_arguments(r, c->nmem, r->content_buf);
+        }
+    }
     return r;
 }
 
-
 static struct http_buf *http_serialize_response(struct http_channel *c,
         struct http_response *r)
 {
-    wrbuf_rewind(c->wrbuf);
     struct http_header *h;
 
-    wrbuf_printf(c->wrbuf, "HTTP/1.1 %s %s\r\n", r->code, r->msg);
+    wrbuf_rewind(c->wrbuf);
+    wrbuf_printf(c->wrbuf, "HTTP/%s %s %s\r\n", c->version, r->code, r->msg);
     for (h = r->headers; h; h = h->next)
         wrbuf_printf(c->wrbuf, "%s: %s\r\n", h->name, h->value);
-    wrbuf_printf(c->wrbuf, "Content-length: %d\r\n", r->payload ? (int) strlen(r->payload) : 0);
-    wrbuf_printf(c->wrbuf, "Content-type: text/xml\r\n");
+    if (r->payload)
+    {
+        wrbuf_printf(c->wrbuf, "Content-Length: %d\r\n", r->payload ?
+                (int) strlen(r->payload) : 0);
+        wrbuf_printf(c->wrbuf, "Content-Type: %s\r\n", r->content_type);
+        if (!strcmp(r->content_type, "text/xml"))
+        {
+            xmlDoc *doc = xmlParseMemory(r->payload, strlen(r->payload));
+            if (doc)
+            {
+                xmlFreeDoc(doc);
+            }
+            else
+            {
+                yaz_log(YLOG_WARN, "Sending non-wellformed "
+                        "response (bug #1162");
+                yaz_log(YLOG_WARN, "payload: %s", r->payload);
+            }
+        }
+    }
     wrbuf_puts(c->wrbuf, "\r\n");
 
     if (r->payload)
@@ -395,21 +619,11 @@ static struct http_buf *http_serialize_response(struct http_channel *c,
 static struct http_buf *http_serialize_request(struct http_request *r)
 {
     struct http_channel *c = r->channel;
-    wrbuf_rewind(c->wrbuf);
     struct http_header *h;
-    struct http_argument *a;
-
-    wrbuf_printf(c->wrbuf, "%s %s", r->method, r->path);
 
-    if (r->arguments)
-    {
-        wrbuf_putc(c->wrbuf, '?');
-        for (a = r->arguments; a; a = a->next) {
-            if (a != r->arguments)
-                wrbuf_putc(c->wrbuf, '&');
-            wrbuf_printf(c->wrbuf, "%s=%s", a->name, a->value);
-        }
-    }
+    wrbuf_rewind(c->wrbuf);
+    wrbuf_printf(c->wrbuf, "%s %s%s%s", r->method, r->path,
+                 *r->search ? "?" : "", r->search);
 
     wrbuf_printf(c->wrbuf, " HTTP/%s\r\n", r->http_version);
 
@@ -417,7 +631,14 @@ static struct http_buf *http_serialize_request(struct http_request *r)
         wrbuf_printf(c->wrbuf, "%s: %s\r\n", h->name, h->value);
 
     wrbuf_puts(c->wrbuf, "\r\n");
-    
+
+    if (r->content_buf)
+        wrbuf_write(c->wrbuf, r->content_buf, r->content_len);
+
+#if 0
+    yaz_log(YLOG_LOG, "WRITING TO PROXY:\n%s\n----",
+            wrbuf_cstr(c->wrbuf));
+#endif
     return http_buf_bywrbuf(c->wrbuf);
 }
 
@@ -429,12 +650,46 @@ static int http_weshouldproxy(struct http_request *rq)
     return 0;
 }
 
+
+struct http_header * http_header_append(struct http_channel *ch, 
+                                        struct http_header * hp, 
+                                        const char *name, 
+                                        const char *value)
+{
+    struct http_header *hpnew = 0; 
+
+    if (!hp | !ch)
+        return 0;
+
+    while (hp && hp->next)
+        hp = hp->next;
+
+    if(name && strlen(name)&& value && strlen(value)){
+        hpnew = nmem_malloc(ch->nmem, sizeof *hpnew);
+        hpnew->name = nmem_strdup(ch->nmem, name);
+        hpnew->value = nmem_strdup(ch->nmem, value);
+        
+        hpnew->next = 0;
+        hp->next = hpnew;
+        hp = hp->next;
+        
+        return hpnew;
+    }
+
+    return hp;
+}
+
+    
+
 static int http_proxy(struct http_request *rq)
 {
     struct http_channel *c = rq->channel;
     struct http_proxy *p = c->proxy;
     struct http_header *hp;
     struct http_buf *requestbuf;
+    char server_via[128] = "";
+    char server_port[16] = "";
+    struct conf_server *ser = global_parameters.server;
 
     if (!p) // This is a new connection. Create a proxy channel
     {
@@ -458,7 +713,8 @@ static int http_proxy(struct http_request *rq)
             yaz_log(YLOG_FATAL|YLOG_ERRNO, "fcntl");
         if (fcntl(sock, F_SETFL, flags | O_NONBLOCK) < 0)
             yaz_log(YLOG_FATAL|YLOG_ERRNO, "fcntl2");
-        if (connect(sock, (struct sockaddr *) proxy_addr, sizeof(*proxy_addr)) < 0)
+        if (connect(sock, (struct sockaddr *) proxy_addr, 
+                    sizeof(*proxy_addr)) < 0)
             if (errno != EINPROGRESS)
             {
                 yaz_log(YLOG_WARN|YLOG_ERRNO, "Proxy connect");
@@ -468,25 +724,40 @@ static int http_proxy(struct http_request *rq)
         p = xmalloc(sizeof(struct http_proxy));
         p->oqueue = 0;
         p->channel = c;
+        p->first_response = 1;
         c->proxy = p;
         // We will add EVENT_OUTPUT below
         p->iochan = iochan_create(sock, proxy_io, EVENT_INPUT);
         iochan_setdata(p->iochan, p);
-        p->iochan->next = channel_list;
-        channel_list = p->iochan;
+        pazpar2_add_channel(p->iochan);
     }
 
-    // Modify Host: header
-    for (hp = rq->headers; hp; hp = hp->next)
-        if (!strcmp(hp->name, "Host"))
-            break;
-    if (!hp)
+    // Do _not_ modify Host: header, just checking it's existence
+
+    if (!http_lookup_header(rq->headers, "Host"))
     {
         yaz_log(YLOG_WARN, "Failed to find Host header in proxy");
         return -1;
     }
-    hp->value = nmem_strdup(c->nmem, proxy_url);
+    
+    // Add new header about paraz2 version, host, remote client address, etc.
+    {
+        hp = rq->headers;
+        hp = http_header_append(c, hp, 
+                                "X-Pazpar2-Version", PACKAGE_VERSION);
+        hp = http_header_append(c, hp, 
+                                "X-Pazpar2-Server-Host", ser->host);
+        sprintf(server_port, "%d",  ser->port);
+        hp = http_header_append(c, hp, 
+                                "X-Pazpar2-Server-Port", server_port);
+        sprintf(server_via,  "1.1 %s:%s (%s/%s)",  
+                ser->host, server_port, PACKAGE_NAME, PACKAGE_VERSION);
+        hp = http_header_append(c, hp, "Via" , server_via);
+        hp = http_header_append(c, hp, "X-Forwarded-For", c->addr);
+    }
+    
     requestbuf = http_serialize_request(rq);
+
     http_buf_enqueue(&p->oqueue, requestbuf);
     iochan_setflag(p->iochan, EVENT_OUTPUT);
     return 0;
@@ -495,8 +766,10 @@ static int http_proxy(struct http_request *rq)
 void http_send_response(struct http_channel *ch)
 {
     struct http_response *rs = ch->response;
+    struct http_buf *hb;
+
     assert(rs);
-    struct http_buf *hb = http_serialize_response(ch, rs);
+    hb = http_serialize_response(ch, rs);
     if (!hb)
     {
         yaz_log(YLOG_WARN, "Failed to serialize HTTP response");
@@ -510,6 +783,22 @@ void http_send_response(struct http_channel *ch)
     }
 }
 
+static void http_error(struct http_channel *hc, int no, const char *msg)
+{
+    struct http_response *rs = http_create_response(hc);
+
+    hc->response = rs;
+    hc->keep_alive = 0;  // not keeping this HTTP session alive
+
+    sprintf(rs->code, "%d", no);
+
+    rs->msg = nmem_strdup(hc->nmem, msg);
+    rs->payload = nmem_malloc(hc->nmem, 100);
+    yaz_snprintf(rs->payload, 99, "<error>HTTP Error %d: %s</error>\n",
+                 no, msg);
+    http_send_response(hc);
+}
+
 static void http_io(IOCHAN i, int event)
 {
     struct http_channel *hc = iochan_getdata(i);
@@ -533,46 +822,40 @@ static void http_io(IOCHAN i, int event)
                 http_destroy(i);
                 return;
             }
-            if (res > 0)
-            {
-                htbuf->buf[res] = '\0';
-                htbuf->len = res;
-                http_buf_enqueue(&hc->iqueue, htbuf);
-            }
-
-            if (hc->state == Http_Busy)
-                return;
-            if ((reqlen = request_check(hc->iqueue)) <= 2)
-                return;
+            htbuf->buf[res] = '\0';
+            htbuf->len = res;
+            http_buf_enqueue(&hc->iqueue, htbuf);
 
-            nmem_reset(hc->nmem);
-            if (!(hc->request = http_parse_request(hc, &hc->iqueue, reqlen)))
+            while (1)
             {
-                yaz_log(YLOG_WARN, "Failed to parse request");
-                http_destroy(i);
-                return;
-            }
-            hc->response = 0;
-            yaz_log(YLOG_LOG, "Request: %s %s%s%s", hc->request->method,
-                    hc->request->path,
-                    *hc->request->search ? "?" : "",
-                    hc->request->search);
-            if (http_weshouldproxy(hc->request))
-                http_proxy(hc->request);
-            else
-            {
-                // Execute our business logic!
-                hc->state = Http_Busy;
-                http_command(hc);
-            }
-            if (hc->iqueue)
-            {
-                yaz_log(YLOG_DEBUG, "We think we have more input to read. Forcing event");
-                iochan_setevent(i, EVENT_INPUT);
+                if (hc->state == Http_Busy)
+                    return;
+                reqlen = request_check(hc->iqueue);
+                if (reqlen <= 2)
+                    return;
+                // we have a complete HTTP request
+                nmem_reset(hc->nmem);
+                if (!(hc->request = http_parse_request(hc, &hc->iqueue, reqlen)))
+                {
+                    yaz_log(YLOG_WARN, "Failed to parse request");
+                    http_error(hc, 400, "Bad Request");
+                    return;
+                }
+                hc->response = 0;
+                yaz_log(YLOG_LOG, "Request: %s %s%s%s", hc->request->method,
+                        hc->request->path,
+                        *hc->request->search ? "?" : "",
+                        hc->request->search);
+                if (http_weshouldproxy(hc->request))
+                    http_proxy(hc->request);
+                else
+                {
+                    // Execute our business logic!
+                    hc->state = Http_Busy;
+                    http_command(hc);
+                }
             }
-
             break;
-
         case EVENT_OUTPUT:
             if (hc->oqueue)
             {
@@ -595,7 +878,7 @@ static void http_io(IOCHAN i, int event)
                     wb->offset += res;
                 }
                 if (!hc->oqueue) {
-                    if (!strcmp(hc->version, "1.0"))
+                    if (!hc->keep_alive)
                     {
                         http_destroy(i);
                         return;
@@ -652,8 +935,11 @@ static void proxy_io(IOCHAN pi, int event)
             else
             {
                 htbuf->buf[res] = '\0';
+                htbuf->offset = 0;
                 htbuf->len = res;
-                http_buf_enqueue(&hc->oqueue, htbuf);
+                // Write any remaining payload
+                if (htbuf->len - htbuf->offset > 0)
+                    http_buf_enqueue(&hc->oqueue, htbuf);
             }
             iochan_setflag(hc->iochan, EVENT_OUTPUT);
             break;
@@ -692,6 +978,9 @@ static void proxy_io(IOCHAN pi, int event)
     }
 }
 
+static void http_fire_observers(struct http_channel *c);
+static void http_destroy_observers(struct http_channel *c);
+
 // Cleanup channel
 static void http_destroy(IOCHAN i)
 {
@@ -707,13 +996,17 @@ static void http_destroy(IOCHAN i)
         http_buf_destroy_queue(s->proxy->oqueue);
         xfree(s->proxy);
     }
+    http_buf_destroy_queue(s->iqueue);
+    http_buf_destroy_queue(s->oqueue);
+    http_fire_observers(s);
+    http_destroy_observers(s);
     s->next = http_channel_freelist;
     http_channel_freelist = s;
     close(iochan_getfd(i));
     iochan_destroy(i);
 }
 
-static struct http_channel *http_create(void)
+static struct http_channel *http_create(const char *addr)
 {
     struct http_channel *r = http_channel_freelist;
 
@@ -733,8 +1026,16 @@ static struct http_channel *http_create(void)
     r->iochan = 0;
     r->iqueue = r->oqueue = 0;
     r->state = Http_Idle;
+    r->keep_alive = 0;
     r->request = 0;
     r->response = 0;
+    if (!addr)
+    {
+        yaz_log(YLOG_WARN, "Invalid HTTP forward address");
+        exit(1);
+    }
+    strcpy(r->addr, addr);
+    r->observers = 0;
     return r;
 }
 
@@ -763,13 +1064,12 @@ static void http_accept(IOCHAN i, int event)
 
     yaz_log(YLOG_DEBUG, "New command connection");
     c = iochan_create(s, http_io, EVENT_INPUT | EVENT_EXCEPT);
-
-    ch = http_create();
+    
+    ch = http_create(inet_ntoa(addr.sin_addr));
     ch->iochan = c;
     iochan_setdata(c, ch);
 
-    c->next = channel_list;
-    channel_list = c;
+    pazpar2_add_channel(c);
 }
 
 /* Create a http-channel listener, syntax [host:]port */
@@ -783,9 +1083,9 @@ void http_init(const char *addr)
     const char *pp;
     int port;
 
-    yaz_log(YLOG_LOG, "HTTP listener is %s", addr);
+    yaz_log(YLOG_LOG, "HTTP listener %s", addr);
 
-    bzero(&myaddr, sizeof myaddr);
+    memset(&myaddr, 0, sizeof myaddr);
     myaddr.sin_family = AF_INET;
     pp = strchr(addr, ':');
     if (pp)
@@ -796,11 +1096,11 @@ void http_init(const char *addr)
 
         strncpy(hostname, addr, len);
         hostname[len] = '\0';
-        if (!(he = gethostbyname(hostname)))
-        {
+        if (!(he = gethostbyname(hostname))){
             yaz_log(YLOG_FATAL, "Unable to resolve '%s'", hostname);
             exit(1);
         }
+        
         memcpy(&myaddr.sin_addr.s_addr, he->h_addr_list[0], he->h_length);
         port = atoi(pp + 1);
     }
@@ -809,6 +1109,7 @@ void http_init(const char *addr)
         port = atoi(addr);
         myaddr.sin_addr.s_addr = INADDR_ANY;
     }
+
     myaddr.sin_port = htons(port);
 
     if (!(p = getprotobyname("tcp"))) {
@@ -821,24 +1122,31 @@ void http_init(const char *addr)
         abort();
 
     if (bind(l, (struct sockaddr *) &myaddr, sizeof myaddr) < 0) 
+    {
         yaz_log(YLOG_FATAL|YLOG_ERRNO, "bind");
+        exit(1);
+    }
     if (listen(l, SOMAXCONN) < 0) 
+    {
         yaz_log(YLOG_FATAL|YLOG_ERRNO, "listen");
+        exit(1);
+    }
 
     c = iochan_create(l, http_accept, EVENT_INPUT | EVENT_EXCEPT);
-    c->next = channel_list;
-    channel_list = c;
+    pazpar2_add_channel(c);
 }
 
-void http_set_proxyaddr(char *host)
+void http_set_proxyaddr(char *host, char *base_url)
 {
     char *p;
     int port;
     struct hostent *he;
 
+    strcpy(myurl, base_url);
     strcpy(proxy_url, host);
     p = strchr(host, ':');
     yaz_log(YLOG_DEBUG, "Proxying for %s", host);
+    yaz_log(YLOG_LOG, "HTTP backend  %s", proxy_url);
     if (p) {
         port = atoi(p + 1);
         *p = '\0';
@@ -856,6 +1164,62 @@ void http_set_proxyaddr(char *host)
     proxy_addr->sin_port = htons(port);
 }
 
+static void http_fire_observers(struct http_channel *c)
+{
+    http_channel_observer_t p = c->observers;
+    while (p)
+    {
+        p->destroy(p->data, c, p->data2);
+        p = p->next;
+    }
+}
+
+static void http_destroy_observers(struct http_channel *c)
+{
+    while (c->observers)
+    {
+        http_channel_observer_t obs = c->observers;
+        c->observers = obs->next;
+        xfree(obs);
+    }
+}
+
+http_channel_observer_t http_add_observer(struct http_channel *c, void *data,
+                                          http_channel_destroy_t des)
+{
+    http_channel_observer_t obs = xmalloc(sizeof(*obs));
+    obs->chan = c;
+    obs->data = data;
+    obs->data2 = 0;
+    obs->destroy= des;
+    obs->next = c->observers;
+    c->observers = obs;
+    return obs;
+}
+
+void http_remove_observer(http_channel_observer_t obs)
+{
+    struct http_channel *c = obs->chan;
+    http_channel_observer_t found, *p = &c->observers;
+    while (*p != obs)
+        p = &(*p)->next;
+    found = *p;
+    assert(found);
+    *p = (*p)->next;
+    xfree(found);
+}
+
+struct http_channel *http_channel_observer_chan(http_channel_observer_t obs)
+{
+    return obs->chan;
+}
+
+void http_observer_set_data2(http_channel_observer_t obs, void *data2)
+{
+    obs->data2 = data2;
+}
+
+
 /*
  * Local variables:
  * c-basic-offset: 4