Add size of empty gif

Server NGINX
1

From: Kirill A. Korinskiy [email protected]

ngx_http_empty_gif_module' is a simplpe module for send 1x1 transparent gif. Since the gif can contain any number of garbages data after the header, I added a directive empty_gif_size’ that sets the
size of “size” for gif 1x1 transparent gif.

src/http/modules/ngx_http_empty_gif_module.c | 162
+++++++++++++++++++++±—
1 files changed, 137 insertions(+), 25 deletions(-)

diff --git a/src/http/modules/ngx_http_empty_gif_module.c
b/src/http/modules/ngx_http_empty_gif_module.c
index
20e4413c086bc9cce0c54b591edc3b5324cf591b…2abbc19ceb9991be85ebd2236d106c4800ae6508
100644
— a/src/http/modules/ngx_http_empty_gif_module.c
+++ b/src/http/modules/ngx_http_empty_gif_module.c
@@ -8,9 +8,22 @@
#include <ngx_http.h>

+typedef struct {

  • ngx_str_t fake;
    +} ngx_http_empty_gif_loc_conf_t;

static char *ngx_http_empty_gif(ngx_conf_t *cf, ngx_command_t *cmd,
void *conf);

+static void *ngx_http_empty_gif_create_local_conf(ngx_conf_t *cf);
+static char *ngx_http_empty_gif_merge_local_conf(ngx_conf_t *cf,

  • void *parent, void *child);

+static char *ngx_http_empty_gif_size(ngx_conf_t *cf,

  • ngx_command_t *cmd, void *conf);

static ngx_command_t ngx_http_empty_gif_commands[] = {

 { ngx_string("empty_gif"),

@@ -20,6 +33,13 @@ static ngx_command_t ngx_http_empty_gif_commands[] =
{
0,
NULL },

  • { ngx_string(“empty_gif_size”),
  •  NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,

  •  ngx_http_empty_gif_size,

  •  NGX_HTTP_LOC_CONF_OFFSET,

  •  offsetof(ngx_http_empty_gif_loc_conf_t, fake),

  •  NULL },

  •  ngx_null_command

};

@@ -75,32 +95,32 @@ static u_char ngx_empty_gif[] = {

static ngx_http_module_t ngx_http_empty_gif_module_ctx = {

  • NULL, /* preconfiguration */
  • NULL, /* postconfiguration */
  • NULL, /* preconfiguration */
  • NULL, /* postconfiguration */
  • NULL, /* create main configuration */
  • NULL, /* init main configuration */
  • NULL, /* create main configuration
    */
  • NULL, /* init main configuration
    */
  • NULL, /* create server configuration */
  • NULL, /* merge server configuration */
  • NULL, /* create server
    configuration */
  • NULL, /* merge server
    configuration */
  • NULL, /* create location configuration */
  • NULL /* merge location configuration */
  • ngx_http_empty_gif_create_local_conf, /* create location
    configuration */
  • ngx_http_empty_gif_merge_local_conf /* merge location
    configuration */
    };

ngx_module_t ngx_http_empty_gif_module = {
NGX_MODULE_V1,

  • &ngx_http_empty_gif_module_ctx, /* module context */
  • ngx_http_empty_gif_commands, /* module directives */
  • NGX_HTTP_MODULE, /* module type */
  • NULL, /* init master */
  • NULL, /* init module */
  • NULL, /* init process */
  • NULL, /* init thread */
  • NULL, /* exit thread */
  • NULL, /* exit process */
  • NULL, /* exit master */
  • &ngx_http_empty_gif_module_ctx, /* module context */
  • ngx_http_empty_gif_commands, /* module directives */
  • NGX_HTTP_MODULE, /* module type */
  • NULL, /* init master */
  • NULL, /* init module */
  • NULL, /* init process */
  • NULL, /* init thread */
  • NULL, /* exit thread */
  • NULL, /* exit process */
  • NULL, /* exit master */
    NGX_MODULE_V1_PADDING
    };

@@ -108,9 +128,12 @@ ngx_module_t ngx_http_empty_gif_module = {
static ngx_int_t
ngx_http_empty_gif_handler(ngx_http_request_t *r)
{

  • ngx_int_t rc;
  • ngx_buf_t *b;
  • ngx_chain_t out;

  • ngx_int_t rc;

  • ngx_buf_t *b;

  • ngx_chain_t out[2];

  • ngx_http_empty_gif_loc_conf_t *conf;

  • conf = ngx_http_get_module_loc_conf(r, ngx_http_empty_gif_module);

    if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) {
    return NGX_HTTP_NOT_ALLOWED;
    @@ -129,6 +152,9 @@ ngx_http_empty_gif_handler(ngx_http_request_t *r)
    if (r->method == NGX_HTTP_HEAD) {
    r->headers_out.status = NGX_HTTP_OK;
    r->headers_out.content_length_n = sizeof(ngx_empty_gif);

  •    if (conf->fake.len) {

  •        r->headers_out.content_length_n += conf->fake.len;

  •    }
   r->headers_out.last_modified_time = 23349600;

   r->headers_out.etag_size = 40;

@@ -144,18 +170,36 @@ ngx_http_empty_gif_handler(ngx_http_request_t *r)
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}

  • out.buf = b;
  • out.next = NULL;

  • out[0].buf = b;

  • out[0].next = NULL;

    b->pos = ngx_empty_gif;
    b->last = ngx_empty_gif + sizeof(ngx_empty_gif);
    b->memory = 1;

  • b->last_buf = 1;

    r->headers_out.status = NGX_HTTP_OK;
    r->headers_out.content_length_n = sizeof(ngx_empty_gif);
    r->headers_out.last_modified_time = 23349600;

  • if (conf->fake.len) {
  •    out[0].next = &out[1];

  •    r->headers_out.content_length_n += conf->fake.len;

  •    b = ngx_pcalloc(r->pool, sizeof(ngx_buf_t));

  •    if (b == NULL) {

  •        return NGX_HTTP_INTERNAL_SERVER_ERROR;

  •    }

  •    out[1].next = NULL;

  •    out[1].buf = b;

  •    b->pos = conf->fake.data;

  •    b->last = conf->fake.data + conf->fake.len;

  •    b->memory = 1;
  • }
  • b->last_buf = 1;
  • r->headers_out.etag_size = 40;
    r->headers_out.etag_time = 5;
    r->headers_out.etag_uniq = 6535;
    @@ -166,7 +210,7 @@ ngx_http_empty_gif_handler(ngx_http_request_t *r)
    return rc;
    }
  • return ngx_http_output_filter(r, &out);
  • return ngx_http_output_filter(r, &out[0]);
    }

@@ -180,3 +224,71 @@ ngx_http_empty_gif(ngx_conf_t *cf, ngx_command_t
*cmd, void *conf)

 return NGX_CONF_OK;

}
+
+
+static void *
+ngx_http_empty_gif_create_local_conf(ngx_conf_t *cf)
+{

  • ngx_http_empty_gif_loc_conf_t *conf;
  • conf = ngx_pcalloc(cf->pool,
    sizeof(ngx_http_empty_gif_loc_conf_t));
  • if (conf == NULL) {
  •    return NGX_CONF_ERROR;
  • }
  • return conf;
    +}

+static char *
+ngx_http_empty_gif_merge_local_conf(ngx_conf_t *cf, void *parent, void
*child)
+{

  • ngx_http_empty_gif_loc_conf_t *prev = parent;
  • ngx_http_empty_gif_loc_conf_t *conf = child;
  • if (prev->fake.len) {
  •    conf->fake = prev->fake;
  • }
  • return NGX_CONF_OK;
    +}

+static char *
+ngx_http_empty_gif_size(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{

  • char *p = conf;
  • ngx_str_t *field, *value;
  • ngx_conf_post_t *post;
  • field = (ngx_str_t *) (p + cmd->offset);
  • if (field->data) {
  •    return "is duplicate";
  • }
  • value = cf->args->elts;
  • field->len = ngx_parse_size(&value[1]);
  • if (field->len == (size_t) NGX_ERROR) {
  •    return "invalid value";
  • }
  • if (field->len < sizeof(ngx_empty_gif)) {
  •    return "is shortly";
  • }
  • field->len -= sizeof(ngx_empty_gif);
  • field->data = ngx_pcalloc(cf->pool, field->len);
  • if (field->data == NULL) {
  •    return NGX_CONF_ERROR;
  • }
  • if (cmd->post) {
  •    post = cmd->post;

  •    return post->post_handler(cf, post, field);
  • }
  • return NGX_CONF_OK;
    +}