Re-factor into separate compression module

Introduce a `conn_interface` to simplify the decision logic which API
we must call.

This also fixes some bugs of the previous commit.

Signed-off-by: Steffen Jaeckel <jaeckel-floss@eyet-services.de>

Author: sjaeckel

Makefile.am

@@ -85,6 +85,12 @@ if NEED_SNPRINTF
 libstrophe_la_SOURCES += src/snprintf.c
 endif
 
+if DISABLE_COMPRESSION
+libstrophe_la_SOURCES += src/compression_dummy.c
+else
+libstrophe_la_SOURCES += src/compression.c
+endif
+
 if DISABLE_TLS
 libstrophe_la_SOURCES += src/tls_dummy.c
 else

configure.ac

@@ -269,6 +269,7 @@ m4_ifdef([PKG_INSTALLDIR], [PKG_INSTALLDIR],
     AC_SUBST([pkgconfigdir], [${with_pkgconfigdir}])])
 
 AM_CONDITIONAL([PARSER_EXPAT], [test x$with_parser != xlibxml2])
+AM_CONDITIONAL([DISABLE_COMPRESSION], [test x$enable_zlib = xno])
 AM_CONDITIONAL([DISABLE_TLS], [test x$enable_tls = xno])
 AM_CONDITIONAL([DISABLE_STATIC], [test x$enable_static = xno])
 AM_CONDITIONAL([NEED_SNPRINTF], [test x$have_snprintf = xno])

examples/bot.c

@@ -77,6 +77,13 @@ int version_handler(xmpp_conn_t *conn, xmpp_stanza_t *stanza, void *userdata)
     return 1;
 }
 
+static int _quit_handler(xmpp_conn_t *conn, void *userdata)
+{
+    (void)userdata;
+    xmpp_disconnect(conn);
+    return 0;
+}
+
 int message_handler(xmpp_conn_t *conn, xmpp_stanza_t *stanza, void *userdata)
 {
     xmpp_ctx_t *ctx = (xmpp_ctx_t *)userdata;
@@ -103,7 +110,7 @@ int message_handler(xmpp_conn_t *conn, xmpp_stanza_t *stanza, void *userdata)
 
     if (strcmp(intext, "quit") == 0) {
         replytext = strdup("bye!");
-        quit = 1;
+        xmpp_timed_handler_add(conn, _quit_handler, 500, NULL);
     } else if (strcmp(intext, "reconnect") == 0) {
         replytext = strdup("alright, let's see what happens!");
         reconnect = 1;
@@ -216,8 +223,8 @@ static void usage(int exit_code)
             "Note: --disable-tls conflicts with --mandatory-tls or "
             "--legacy-ssl\n"
             "  --zlib                   Enable compression via zlib.\n"
-            "  --dont-flush             When using zlib, don't flush after "
-            "compression.\n");
+            "  --dont-reset             When using zlib, don't do a full-flush "
+            "after compression.\n");
 
     exit(exit_code);
 }
@@ -249,8 +256,8 @@ int main(int argc, char **argv)
             flags |= XMPP_CONN_FLAG_LEGACY_AUTH;
         else if (strcmp(argv[i], "--zlib") == 0)
             flags |= XMPP_CONN_FLAG_ENABLE_COMPRESSION;
-        else if (strcmp(argv[i], "--dont-flush") == 0)
-            flags |= XMPP_CONN_FLAG_COMPRESSION_DONT_FLUSH;
+        else if (strcmp(argv[i], "--dont-reset") == 0)
+            flags |= XMPP_CONN_FLAG_COMPRESSION_DONT_RESET;
         else if ((strcmp(argv[i], "--jid") == 0) && (++i < argc))
             jid = argv[i];
         else if ((strcmp(argv[i], "--pass") == 0) && (++i < argc))

examples/complex.c

@@ -240,8 +240,8 @@ static void usage(int exit_code)
             "  --legacy-ssl             Use old style SSL.\n"
             "  --legacy-auth            Allow legacy authentication.\n"
             "  --zlib                   Enable compression via zlib.\n"
-            "  --dont-flush             When using zlib, don't flush after "
-            "compression.\n"
+            "  --dont-reset             When using zlib, don't do a full-flush "
+            "after compression.\n"
             "  --verbose                Increase the verbosity level.\n"
             "  --tcp-keepalive          Configure TCP keepalive.\n\n"
             "Note: --disable-tls conflicts with --mandatory-tls or "
@@ -278,8 +278,8 @@ int main(int argc, char **argv)
             flags |= XMPP_CONN_FLAG_LEGACY_AUTH;
         else if (strcmp(argv[i], "--zlib") == 0)
             flags |= XMPP_CONN_FLAG_ENABLE_COMPRESSION;
-        else if (strcmp(argv[i], "--dont-flush") == 0)
-            flags |= XMPP_CONN_FLAG_COMPRESSION_DONT_FLUSH;
+        else if (strcmp(argv[i], "--dont-reset") == 0)
+            flags |= XMPP_CONN_FLAG_COMPRESSION_DONT_RESET;
         else if (strcmp(argv[i], "--verbose") == 0)
             verbosity++;
         else if (strcmp(argv[i], "--tcp-keepalive") == 0)

src/auth.c

@@ -255,19 +255,10 @@ static void _handle_sasl_children(xmpp_conn_t *conn, const char *text)
     }
 }
 
-static void _handle_compression_children(xmpp_conn_t *conn, const char *text)
-{
-    if (strcasecmp(text, "zlib") == 0) {
-        conn->compression_supported = 1;
-    }
-}
-
 static int
 _handle_features(xmpp_conn_t *conn, xmpp_stanza_t *stanza, void *userdata)
 {
-    xmpp_stanza_t *child, *children;
-    const char *ns;
-    char *text;
+    xmpp_stanza_t *child;
 
     UNUSED(userdata);
 
@@ -297,13 +288,6 @@ _handle_features(xmpp_conn_t *conn, xmpp_stanza_t *stanza, void *userdata)
     if (conn->sasl_support & ~(SASL_MASK_PLAIN | SASL_MASK_ANONYMOUS))
         conn->sasl_support &= ~SASL_MASK_PLAIN;
 
-    /* check for compression */
-    child = xmpp_stanza_get_child_by_name_and_ns(stanza, "compression",
-                                                 XMPP_NS_COMPRESSION);
-    if (conn->compression_allowed && child) {
-        _foreach_child(conn, child, "method", _handle_compression_children);
-    }
-
     _auth(conn);
 
     return 0;
@@ -371,7 +355,7 @@ _handle_sasl_result(xmpp_conn_t *conn, xmpp_stanza_t *stanza, void *userdata)
                       (char *)userdata);
 
         /* reset parser */
-        conn_prepare_reset(conn, conn->compression_allowed
+        conn_prepare_reset(conn, conn->compression.allowed
                                      ? _handle_open_compress
                                      : _handle_open_sasl);
 
@@ -1057,6 +1041,8 @@ static int _handle_compress_result(xmpp_conn_t *const conn,
 {
     const char *name = xmpp_stanza_get_name(stanza);
 
+    UNUSED(userdata);
+
     if (!name)
         return 0;
     if (strcmp(name, "compressed") == 0) {
@@ -1067,7 +1053,7 @@ static int _handle_compress_result(xmpp_conn_t *const conn,
         conn_prepare_reset(conn, _handle_open_sasl);
 
         /* make compression effective */
-        conn->compress = 1;
+        compression_init(conn);
 
         /* send stream tag */
         conn_open_stream(conn);
@@ -1081,15 +1067,26 @@ static int _handle_features_compress(xmpp_conn_t *conn,
 {
     const char *compress = "<compress xmlns='" XMPP_NS_COMPRESSION
                            "'><method>zlib</method></compress>";
-
-    UNUSED(userdata);
+    xmpp_stanza_t *child;
 
     /* remove missing features handler */
     xmpp_timed_handler_delete(conn, _handle_missing_features);
 
-    send_raw(conn, compress, strlen(compress), XMPP_QUEUE_STROPHE, NULL);
-    handler_add(conn, _handle_compress_result, XMPP_NS_COMPRESSION, NULL, NULL,
-                NULL);
+    /* check for compression */
+    child = xmpp_stanza_get_child_by_name_and_ns(stanza, "compression",
+                                                 XMPP_NS_FEATURE_COMPRESSION);
+    if (conn->compression.allowed && child) {
+        _foreach_child(conn, child, "method",
+                       compression_handle_feature_children);
+    }
+
+    if (conn->compression.supported) {
+        send_raw(conn, compress, strlen(compress), XMPP_QUEUE_STROPHE, NULL);
+        handler_add(conn, _handle_compress_result, XMPP_NS_COMPRESSION, NULL,
+                    NULL, NULL);
+    } else {
+        return _handle_features_sasl(conn, stanza, userdata);
+    }
 
     return 0;
 }

src/common.h

@@ -19,7 +19,6 @@
 
 #include <stdio.h>
 #include <stdarg.h>
-#include <zlib.h>
 
 #include "strophe.h"
 #include "ostypes.h"
@@ -202,7 +201,29 @@ struct _xmpp_sm_t {
     xmpp_stanza_t *bind;
 };
 
+struct conn_interface {
+    int (*read)(struct conn_interface *intf, void *buff, size_t len);
+    int (*write)(struct conn_interface *intf, const void *buff, size_t len);
+    int (*flush)(struct conn_interface *intf);
+    int (*pending)(struct conn_interface *intf);
+    int (*get_error)(struct conn_interface *intf);
+    int (*error_is_recoverable)(int err);
+    xmpp_conn_t *conn;
+};
+
+int conn_interface_write(struct conn_interface *intf,
+                         const void *buff,
+                         size_t len);
+int conn_int_nop(struct conn_interface *intf);
+int conn_recoverable_nop(int err);
+
+int compression_init(xmpp_conn_t *conn);
+void compression_free(xmpp_conn_t *conn);
+void compression_handle_feature_children(xmpp_conn_t *conn, const char *text);
+
 struct _xmpp_conn_t {
+    struct conn_interface intf;
+
     unsigned int ref;
     xmpp_ctx_t *ctx;
     xmpp_conn_type_t type;
@@ -250,12 +271,10 @@ struct _xmpp_conn_t {
     int sm_disable;
     xmpp_sm_state_t *sm_state;
 
-    int compression_allowed, compression_supported;
-    int compress, compression_dont_flush;
-    struct zlib_compression {
-        void *buffer, *buffer_end;
-        z_stream stream;
-    } compression, decompression;
+    struct {
+        struct xmpp_compression *state;
+        int allowed, supported, dont_reset;
+    } compression;
 
     char *lang;
     char *domain;