Add size of empty gif

Kirill_ASKorinskiy · March 17, 2009, 8:28pm

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;
+}

Kirill_ASKorinskiy · March 18, 2009, 12:49am

From: Kirill A. Korinskiy [email protected]

Now for send of very large empty gif did not allocated a lot of
memory, because I allocated buffer and used it multiple times. Size of
buffer is a first optional argument of `empty_gif_size’ directive.

src/http/modules/ngx_http_empty_gif_module.c | 109
++++++++++++++++±--------
1 files changed, 71 insertions(+), 38 deletions(-)

diff --git a/src/http/modules/ngx_http_empty_gif_module.c
b/src/http/modules/ngx_http_empty_gif_module.c
index
2abbc19ceb9991be85ebd2236d106c4800ae6508…17b46ac0efb06673232e808ca1d0b44d5994a1a2
100644
— a/src/http/modules/ngx_http_empty_gif_module.c
+++ b/src/http/modules/ngx_http_empty_gif_module.c
@@ -9,7 +9,12 @@

typedef struct {

ngx_str_t fake;

size_t size;
ngx_str_t str;
+} ngx_http_empty_gif_fake_t;

+typedef struct {

ngx_http_empty_gif_fake_t fake;
} ngx_http_empty_gif_loc_conf_t;

@@ -34,7 +39,7 @@ static ngx_command_t ngx_http_empty_gif_commands[] =
{
NULL },

 { ngx_string("empty_gif_size"),

```
 NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
```

 NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1|NGX_CONF_TAKE2,
 ngx_http_empty_gif_size,
 NGX_HTTP_LOC_CONF_OFFSET,
 offsetof(ngx_http_empty_gif_loc_conf_t, fake),

@@ -129,8 +134,9 @@ 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[2];

ngx_buf_t *b = NULL;
ngx_uint_t i, out_count;
ngx_chain_t *out;
ngx_http_empty_gif_loc_conf_t *conf;

conf = ngx_http_get_module_loc_conf(r, ngx_http_empty_gif_module);
@@ -152,8 +158,8 @@ 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;

```
   if (conf->fake.size) {
```

       r->headers_out.content_length_n += conf->fake.size;
   }
   r->headers_out.last_modified_time = 23349600;

@@ -165,39 +171,50 @@ ngx_http_empty_gif_handler(ngx_http_request_t *r)
return ngx_http_send_header(r);
}

b = ngx_pcalloc(r->pool, sizeof(ngx_buf_t));
if (b == NULL) {

   return NGX_HTTP_INTERNAL_SERVER_ERROR;

out_count = 1;
if (conf->fake.size) {

   out_count += conf->fake.size / conf->fake.str.len;

   if (conf->fake.size % conf->fake.str.len) {

```
       out_count++;
```
```
   }
```
}

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;
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;

out = ngx_palloc(r->pool, sizeof(ngx_chain_t) * out_count);
if (out == NULL) {

   return NGX_HTTP_INTERNAL_SERVER_ERROR;

}
for (i = 0; i < out_count; i++) {
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;
```

```
   out[i].buf = b;
```
```
   if (0 == i) {
```
```
       out[i].next = NULL;
```

       b->pos = b->start = ngx_empty_gif;

       b->last = b->end = ngx_empty_gif + sizeof(ngx_empty_gif);

   } else if ((conf->fake.size / conf->fake.str.len) + 1 == i) {

```
       out[i-1].next = &out[i];
```
```
       out[i].next = NULL;
```

       b->pos = b->start = conf->fake.str.data;

       b->last = b->end = conf->fake.str.data + conf->fake.size %

conf->fake.str.len;

```
   } else {
```
```
       out[i-1].next = &out[i];
```
```
       out[i].next = NULL;
```

       b->pos = b->start = conf->fake.str.data;

       b->last = b->end = conf->fake.str.data +

conf->fake.str.len;

```
   }
```

```
   b->pos = conf->fake.data;
```

   b->last = conf->fake.data + conf->fake.len;
   b->memory = 1;

}

r->headers_out.status = NGX_HTTP_OK;
r->headers_out.content_length_n = sizeof(ngx_empty_gif) +
conf->fake.size;
r->headers_out.last_modified_time = 23349600;
b->last_buf = 1;

r->headers_out.etag_size = 40;
@@ -210,7 +227,7 @@ ngx_http_empty_gif_handler(ngx_http_request_t *r)
return rc;
}

return ngx_http_output_filter(r, &out[0]);

return ngx_http_output_filter(r, out);
}

@@ -245,7 +262,7 @@ 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) {

if (prev->fake.size) {
conf->fake = prev->fake;
}

@@ -257,31 +274,47 @@ ngx_http_empty_gif_size(ngx_conf_t *cf,
ngx_command_t *cmd, void *conf)
{
char *p = conf;

ngx_str_t *field, *value;

ngx_str_t *value;
ngx_int_t i = 1;
ngx_conf_post_t *post;
ngx_http_empty_gif_fake_t *field;

field = (ngx_str_t *) (p + cmd->offset);

field = (ngx_http_empty_gif_fake_t *) (p + cmd->offset);

if (field->data) {

if (field->str.data) {
return “is duplicate”;
}

value = cf->args->elts;

field->len = ngx_parse_size(&value[1]);

if (cf->args->nelts == 3) {

   field->str.len = ngx_parse_size(&value[i]);

   if (field->str.len == (size_t) NGX_ERROR) {

```
       return "invalid value";
```
```
   }
```
```
   i++;
```
} else {
```
   field->str.len = 1024;
```
}
field->size = ngx_parse_size(&value[i]);

if (field->len == (size_t) NGX_ERROR) {

if (field->size == (size_t) NGX_ERROR) {
return “invalid value”;
}

if (field->len < sizeof(ngx_empty_gif)) {

if (field->size < sizeof(ngx_empty_gif)) {
return “is shortly”;
}

field->len -= sizeof(ngx_empty_gif);

field->size -= sizeof(ngx_empty_gif);
if (field->str.len > field->size) {
```
   field->str.len = field->size;
```
}

field->data = ngx_pcalloc(cf->pool, field->len);
if (field->data == NULL) {

field->str.data = ngx_pcalloc(cf->pool, field->str.len);
if (field->str.data == NULL) {
return NGX_CONF_ERROR;
}

Kirill_ASKorinskiy · March 18, 2009, 12:49am

From: Kirill A. Korinskiy [email protected]

src/http/modules/ngx_http_empty_gif_module.c | 3 +±
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/src/http/modules/ngx_http_empty_gif_module.c
b/src/http/modules/ngx_http_empty_gif_module.c
index
17b46ac0efb06673232e808ca1d0b44d5994a1a2…e1a5749f44369b092913720ab89f565f8deb3130
100644
— a/src/http/modules/ngx_http_empty_gif_module.c
+++ b/src/http/modules/ngx_http_empty_gif_module.c
@@ -39,7 +39,8 @@ static ngx_command_t ngx_http_empty_gif_commands[] =
{
NULL },

 { ngx_string("empty_gif_size"),

 NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1|NGX_CONF_TAKE2,

NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF

                   |NGX_CONF_TAKE12,
 ngx_http_empty_gif_size,
 NGX_HTTP_LOC_CONF_OFFSET,
 offsetof(ngx_http_empty_gif_loc_conf_t, fake),

Add size of empty gif

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.

Now for send of very large empty gif did not allocated a lot of memory, because I allocated buffer and used it multiple times. Size of buffer is a first optional argument of `empty_gif_size’ directive.

`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.

Now for send of very large empty gif did not allocated a lot of
memory, because I allocated buffer and used it multiple times. Size of
buffer is a first optional argument of `empty_gif_size’ directive.