--- a/src/core/ngx_alloc.c
+++ b/src/core/ngx_alloc.c
@@ -67,6 +67,10 @@ void ngx_destroy_pool(ngx_pool_t *pool)
 #if (NGX_DEBUG_ALLOC)
     for (p = pool, n = pool->next; /* void */; p = n, n = n->next) {
         ngx_log_debug(pool->log, "free: %08x" _ p);
+
+        if (n == NULL) {
+            break;
+        }
     }
 #endif
 

--- a/src/http/modules/ngx_http_charset_filter.c
+++ b/src/http/modules/ngx_http_charset_filter.c
@@ -60,6 +60,11 @@ static int ngx_http_charset_header_filte
 {
     ngx_http_charset_loc_conf_t  *lcf;
 
+    if (ngx_strncasecmp(r->headers_out.content_type->value.data, "text/", 5)
+                                                                        != 0) {
+        return next_header_filter(r);
+    }
+
     lcf = ngx_http_get_module_loc_conf(r, ngx_http_charset_filter_module);
 
     if (r->headers_out.status == NGX_HTTP_MOVED_PERMANENTLY

new file mode 100644
--- /dev/null
+++ b/src/http/modules/ngx_http_gzip_filter.c
@@ -0,0 +1,245 @@
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+#include <zlib.h>
+
+
+typedef struct {
+    int  hunk_size;
+    int  max_hunks;
+    int  no_buffer;
+} ngx_http_gzip_conf_t;
+
+
+typedef struct {
+    ngx_chain_t   *in;
+    ngx_chain_t   *free;
+    ngx_chain_t   *busy;
+    ngx_chain_t   *out;
+    ngx_chain_t  **last_out;
+    ngx_hunk_t    *in_hunk;
+    ngx_hunk_t    *out_hunk;
+    void          *alloc;
+
+    z_stream       zstream;
+} ngx_http_gzip_ctx_t;
+
+
+static int ngx_http_gzip_filter_init(ngx_cycle_t *cycle);
+
+
+static ngx_http_module_t  ngx_http_gzip_filter_module_ctx = {
+    NULL,                                  /* create main configuration */
+    NULL,                                  /* init main configuration */
+
+    NULL,                                  /* create server configuration */
+    NULL,                                  /* merge server configuration */
+
+    NULL,                                  /* create location configuration */
+    NULL,                                  /* merge location configuration */
+};
+
+
+ngx_module_t  ngx_http_gzip_filter_module = {
+    NGX_MODULE,
+    &ngx_http_gzip_filter_module_ctx,      /* module context */
+    NULL,                                  /* module directives */
+    NGX_HTTP_MODULE,                       /* module type */
+    ngx_http_gzip_filter_init,             /* init module */
+    NULL                                   /* init child */
+};
+
+
+static const char gzheader[10] =
+                               { 0x1f, 0x8b, Z_DEFLATED, 0, 0, 0, 0, 0, 0, 3 };
+
+
+static int (*next_header_filter) (ngx_http_request_t *r);
+static int (*next_body_filter) (ngx_http_request_t *r, ngx_chain_t *ch);
+
+
+static int ngx_http_gzip_header_filter(ngx_http_request_t *r)
+{
+    if (r->headers_out.status != NGX_HTTP_OK
+        || (ngx_strncasecmp(r->headers_out.content_type->value.data,
+                            "text/", 5) != 0)
+    {
+        return next_header_filter(r);
+    }
+
+    ngx_http_create_ctx(r, ctx, ngx_http_gzip_filter_module,
+                        sizeof(ngx_http_gzip_filter_ctx_t), NGX_ERROR);
+
+    ctx->length = r->headers_out.content_length;
+    r->headers_out.content_length = -1;
+
+    return next_header_filter(r);
+}
+
+
+static int ngx_http_gzip_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
+{
+    ngx_http_gzip_ctx_t   *ctx;
+    ngx_http_gzip_conf_t  *conf;
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_gzip_filter_module);
+
+    if (ctx == NULL) {
+        next_body_filter(r, in);
+    }
+
+    conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
+
+    if (ctx->alloc == NULL) {
+#if 0
+        ngx_test_null(ctx->alloc, ngx_alloc(200K, r->log), NGX_ERROR);
+#else
+        ctx->alloc = ~NULL;
+#endif
+        rc = deflateInit2(&ctx->zstream, /**/ 1, Z_DEFLATED,
+                          /**/ -MAX_WBITS, /**/ MAX_MEM_LEVEL - 1,
+                          Z_DEFAULT_STRATEGY);
+
+        if (rc != Z_OK) {
+            ngx_log_error(NGX_LOG_ALERT, r->log, 0,
+                          "deflateInit2() failed: %d", rc);
+            return ngx_http_gzip_error(ctx);
+        }
+
+        ngx_test_null(h, ngx_calloc_hunk(r->pool), ngx_http_gzip_error(ctx));
+
+        h->type = NGX_HUNK_IN_MEMORY|NGX_HUNK_MEMORY;
+        h->pos = gzheader;
+        h->last = h->pos + 10;
+
+        ngx_test_null(ce, ngx_alloc_chain_entry(r->pool),
+                      ngx_http_gzip_error(ctx));
+        ce->hunk = h;
+        ce->next = NULL;
+        ctx->out = ce;
+        ctx->last_out = &ce->next;
+
+        ctx->crc32 = crc32(0L, Z_NULL, 0);
+        ctx->flush = Z_NO_FLUSH;
+    }
+
+    if (in) {
+        add_to_chain(ctx->in, in)
+    }
+
+    for ( ;; ) {
+
+        for ( ;; ) {
+
+            if (ctx->flush == Z_NO_FLUSH
+                && ctx->zstream->avail_in == 0
+                && ctx->in)
+             {
+                ctx->in_hunk = ctx->in->hunk;
+                ctx->in = ctx->in->next;
+
+                ctx->zstream->next_in = ctx->in_hunk->pos;
+                ctx->zstream->avail_in = ctx->in_hunk->last - ctx->in_hunk->pos;
+
+                if (ctx->in_hunk->type & NGX_HUNK_LAST) {
+                    ctx->flush = Z_FINISH;
+
+                } else if (ctx->in_hunk->type & NGX_HUNK_FLUSH) {
+                    ctx->flush = Z_SYNC_FINISH;
+                }
+            }
+
+            if (ctx->zstream->avail_out == 0) {
+                if (ctx->free) {
+                    ctx->out_hunk = ctx->free->hunk;
+                    ctx->free = ctx->free->next;
+
+                } else if (ctx->max_hunks < ctx->cur_hunks) {
+                    ngx_test_null(ctx->out_hunk,
+                                  ngx_create_temp_hunk(r->pool, conf->size,
+                                                       0, 0),
+                                  ngx_http_gzip_error(ctx));
+                    ctx->cur_hunks++;
+
+                } else {
+                     break;
+                }
+
+                ctx->zstream->next_out = ctx->out_hunk->pos;
+                ctx->zstream->avail_out = conf->size;
+            }
+
+            rc = deflate(ctx->zstream, ctx->flush);
+            if (rc != Z_OK && rc != Z_STREAM_END) {
+                ngx_log_error(NGX_LOG_ALERT, r->log, 0,
+                              "deflate() failed: %d, %d", ctx->flush, rc);
+                return ngx_http_gzip_error(ctx);
+            }
+
+            ctx->in_hunk->pos = ctx->zstream->next_in;
+
+            if (rc == Z_STREAM_END) {
+                deflateEnd(ctx->zstream);
+                ngx_free();
+            }
+
+            if (ctx->zstream->avail_out == 0) {
+                ctx->out_hunk->last += conf->size;
+                ngx_add_hunk_to_chain(*ctx->last_out, ctx->out_hunk,
+                                      r->pool, ngx_http_gzip_error(ctx));
+
+            } else {
+                ctx->out_hunk->last = ctx->zstream->next_out;
+
+                if (ctx->flush == Z_SYNC_FLUSH) {
+                    ctx->out_hunk->type |= NGX_HUNK_FLUSH;
+                    ngx_add_hunk_to_chain(*ctx->last_out, ctx->out_hunk,
+                                          r->pool, ngx_http_gzip_error(ctx));
+                    ctx->flush = Z_NO_FLUSH;
+                    break;
+
+                } else if (ctx->flush == Z_FINISH) {
+                    ctx->out_hunk->type |= NGX_HUNK_LAST;
+                    ngx_add_hunk_to_chain(*ctx->last_out, ctx->out_hunk,
+                                          r->pool, ngx_http_gzip_error(ctx));
+                    break;
+
+                } else if (conf->no_buffer && ctx->in == NULL) {
+                    ngx_add_hunk_to_chain(*ctx->last_out, ctx->out_hunk,
+                                          r->pool, ngx_http_gzip_error(ctx));
+                    break;
+                }
+            }
+        }
+
+        if (next_body_filter(r, ctx->out) == NGX_ERROR) {
+            return ngx_http_gzip_error(ctx);
+        }
+
+        ngx_chain_update_chains(&ctx->free, &ctx->busy, &ctx->out);
+    }
+}
+
+
+ngx_inline static int ngx_http_gzip_error(ngx_http_gzip_ctx_t *ctx)
+{
+#if 0
+    ngx_free(ctx->alloc);
+#endif
+
+    return NGX_ERROR;
+}
+
+
+static int ngx_http_gzip_filter_init(ngx_cycle_t *cycle)
+{
+    next_header_filter = ngx_http_top_header_filter;
+    ngx_http_top_header_filter = ngx_http_gzip_header_filter;
+
+    next_body_filter = ngx_http_top_body_filter;
+    ngx_http_top_body_filter = ngx_http_gzip_body_filter;
+
+    return NGX_OK;
+}

--- a/src/http/modules/ngx_http_range_filter.c
+++ b/src/http/modules/ngx_http_range_filter.c
@@ -208,7 +208,7 @@ static int ngx_http_range_header_filter(
 #endif
 
             ngx_http_create_ctx(r, ctx, ngx_http_range_filter_module,
-                               sizeof(ngx_http_range_filter_ctx_t), NGX_ERROR);
+                                sizeof(ngx_http_range_filter_ctx_t), NGX_ERROR);
 
             len = 4 + 10 + 2 + 14 + r->headers_out.content_type->value.len
                                   + 2 + 21 + 1;