libwebsockets/plugins/protocol_post_demo.c
Andy Green 53d195022f cmake: Enable WITH_MINIMAL_EXAMPLES by default
Although many of the examples must be run from the example directory as
cwd, everyone getting started probably wants to try the examples, cmake
knows how to do it, so let's enable it by default.
2021-11-11 11:52:46 +00:00

320 lines
7.2 KiB
C

/*
* ws protocol handler plugin for "POST demo"
*
* Written in 2010-2019 by Andy Green <andy@warmcat.com>
*
* This file is made available under the Creative Commons CC0 1.0
* Universal Public Domain Dedication.
*
* The person who associated a work with this deed has dedicated
* the work to the public domain by waiving all of his or her rights
* to the work worldwide under copyright law, including all related
* and neighboring rights, to the extent allowed by law. You can copy,
* modify, distribute and perform the work, even for commercial purposes,
* all without asking permission.
*
* These test plugins are intended to be adapted for use in your code, which
* may be proprietary. So unlike the library itself, they are licensed
* Public Domain.
*/
#if !defined (LWS_PLUGIN_STATIC)
#if !defined(LWS_DLL)
#define LWS_DLL
#endif
#if !defined(LWS_INTERNAL)
#define LWS_INTERNAL
#endif
#include <libwebsockets.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef WIN32
#include <io.h>
#endif
#include <stdio.h>
struct per_session_data__post_demo {
struct lws_spa *spa;
char result[LWS_PRE + LWS_RECOMMENDED_MIN_HEADER_SPACE];
char filename[64];
long file_length;
#if !defined(LWS_WITH_ESP32)
lws_filefd_type fd;
#endif
uint8_t completed:1;
uint8_t sent_headers:1;
uint8_t sent_body:1;
};
static const char * const param_names[] = {
"text",
"send",
"file",
"upload",
};
enum enum_param_names {
EPN_TEXT,
EPN_SEND,
EPN_FILE,
EPN_UPLOAD,
};
static int
file_upload_cb(void *data, const char *name, const char *filename,
char *buf, int len, enum lws_spa_fileupload_states state)
{
struct per_session_data__post_demo *pss =
(struct per_session_data__post_demo *)data;
#if !defined(LWS_WITH_ESP32)
int n;
(void)n;
#endif
switch (state) {
case LWS_UFS_OPEN:
lws_strncpy(pss->filename, filename, sizeof(pss->filename));
/* we get the original filename in @filename arg, but for
* simple demo use a fixed name so we don't have to deal with
* attacks */
#if !defined(LWS_WITH_ESP32)
pss->fd = (lws_filefd_type)(lws_intptr_t)lws_open("/tmp/post-file",
O_CREAT | O_TRUNC | O_RDWR, 0600);
#endif
break;
case LWS_UFS_FINAL_CONTENT:
case LWS_UFS_CONTENT:
if (len) {
pss->file_length += len;
/* if the file length is too big, drop it */
if (pss->file_length > 100000)
return 1;
#if !defined(LWS_WITH_ESP32)
n = (int)write((int)(lws_intptr_t)pss->fd, buf, (unsigned int)len);
lwsl_info("%s: write %d says %d\n", __func__, len, n);
#else
lwsl_notice("%s: Received chunk size %d\n", __func__, len);
#endif
}
if (state == LWS_UFS_CONTENT)
break;
#if !defined(LWS_WITH_ESP32)
close((int)(lws_intptr_t)pss->fd);
#if defined(__MINGW32__)
pss->fd = -1;
#else
pss->fd = LWS_INVALID_FILE;
#endif
#endif
break;
case LWS_UFS_CLOSE:
break;
}
return 0;
}
/*
* returns length in bytes
*/
static int
format_result(struct per_session_data__post_demo *pss)
{
unsigned char *p, *start, *end;
int n;
p = (unsigned char *)pss->result + LWS_PRE;
start = p;
end = p + sizeof(pss->result) - LWS_PRE - 1;
if (!pss->spa) {
p += lws_snprintf((char *)p, lws_ptr_diff_size_t(end, p),
"pss->spa already NULL");
goto bail;
}
p += lws_snprintf((char *)p, lws_ptr_diff_size_t(end, p),
"<!DOCTYPE html><html lang=\"en\"><head>"
"<meta charset=utf-8 http-equiv=\"Content-Language\" "
"content=\"en\"/>"
"<title>LWS Server Status</title>"
"</head><body><h1>Form results (after urldecoding)</h1>"
"<table><tr><td>Name</td><td>Length</td><td>Value</td></tr>");
for (n = 0; n < (int)LWS_ARRAY_SIZE(param_names); n++) {
if (!lws_spa_get_string(pss->spa, n))
p += lws_snprintf((char *)p, lws_ptr_diff_size_t(end, p),
"<tr><td><b>%s</b></td><td>0"
"</td><td>NULL</td></tr>",
param_names[n]);
else
p += lws_snprintf((char *)p, lws_ptr_diff_size_t(end, p),
"<tr><td><b>%s</b></td><td>%d"
"</td><td>%s</td></tr>",
param_names[n],
lws_spa_get_length(pss->spa, n),
lws_spa_get_string(pss->spa, n));
}
p += lws_snprintf((char *)p, lws_ptr_diff_size_t(end, p),
"</table><br><b>filename:</b> %s, "
"<b>length</b> %ld",
pss->filename, pss->file_length);
p += lws_snprintf((char *)p, lws_ptr_diff_size_t(end, p), "</body></html>");
bail:
return (int)lws_ptr_diff(p, start);
}
static int
callback_post_demo(struct lws *wsi, enum lws_callback_reasons reason,
void *user, void *in, size_t len)
{
struct per_session_data__post_demo *pss =
(struct per_session_data__post_demo *)user;
unsigned char *p, *start, *end;
int n;
switch (reason) {
case LWS_CALLBACK_HTTP_BODY:
/* create the POST argument parser if not already existing */
if (!pss->spa) {
pss->spa = lws_spa_create(wsi, param_names,
LWS_ARRAY_SIZE(param_names), 1024,
file_upload_cb, pss);
if (!pss->spa)
return -1;
pss->filename[0] = '\0';
pss->file_length = 0;
}
/* let it parse the POST data */
if (lws_spa_process(pss->spa, in, (int)len))
return -1;
break;
case LWS_CALLBACK_HTTP_BODY_COMPLETION:
lwsl_debug("LWS_CALLBACK_HTTP_BODY_COMPLETION: %s\n", lws_wsi_tag(wsi));
/* call to inform no more payload data coming */
lws_spa_finalize(pss->spa);
pss->completed = 1;
lws_callback_on_writable(wsi);
break;
case LWS_CALLBACK_HTTP_WRITEABLE:
if (!pss->completed)
break;
p = (unsigned char *)pss->result + LWS_PRE;
start = p;
end = p + sizeof(pss->result) - LWS_PRE - 1;
if (!pss->sent_headers) {
n = format_result(pss);
if (lws_add_http_header_status(wsi, HTTP_STATUS_OK,
&p, end))
goto bail;
if (lws_add_http_header_by_token(wsi,
WSI_TOKEN_HTTP_CONTENT_TYPE,
(unsigned char *)"text/html", 9,
&p, end))
goto bail;
if (lws_add_http_header_content_length(wsi, (unsigned int)n, &p, end))
goto bail;
if (lws_finalize_http_header(wsi, &p, end))
goto bail;
/* first send the headers ... */
n = lws_write(wsi, start, lws_ptr_diff_size_t(p, start),
LWS_WRITE_HTTP_HEADERS);
if (n < 0)
goto bail;
pss->sent_headers = 1;
lws_callback_on_writable(wsi);
break;
}
if (!pss->sent_body) {
n = format_result(pss);
n = lws_write(wsi, (unsigned char *)start, (unsigned int)n,
LWS_WRITE_HTTP_FINAL);
pss->sent_body = 1;
if (n < 0)
return 1;
goto try_to_reuse;
}
break;
case LWS_CALLBACK_HTTP_DROP_PROTOCOL:
/* called when our wsi user_space is going to be destroyed */
if (pss->spa) {
lws_spa_destroy(pss->spa);
pss->spa = NULL;
}
break;
default:
break;
}
return 0;
bail:
return 1;
try_to_reuse:
if (lws_http_transaction_completed(wsi))
return -1;
return 0;
}
#define LWS_PLUGIN_PROTOCOL_POST_DEMO \
{ \
"protocol-post-demo", \
callback_post_demo, \
sizeof(struct per_session_data__post_demo), \
1024, \
0, NULL, 0 \
}
#if !defined (LWS_PLUGIN_STATIC)
LWS_VISIBLE const struct lws_protocols post_demo_protocols[] = {
LWS_PLUGIN_PROTOCOL_POST_DEMO
};
LWS_VISIBLE const lws_plugin_protocol_t post_demo = {
.hdr = {
"post demo",
"lws_protocol_plugin",
LWS_BUILD_HASH,
LWS_PLUGIN_API_MAGIC
},
.protocols = post_demo_protocols,
.count_protocols = LWS_ARRAY_SIZE(post_demo_protocols),
.extensions = NULL,
.count_extensions = 0,
};
#endif