这一个比上一次更进一步,可以POST和GET请求,基本上满足网上的各种网站的API调用.配合cJson能完成各种事情.
因为TCP协议他其实并没法知道上层协议,上层协议其实是TCP协议一定组合后的一些约定方法.新的Web Client方式也更简单.
int WebClient(const char *url, const char *post, uint8_t **pageBuf)
{
uint16_t i, j, k;
char *server_addr = NULL;
char *web_addr = NULL;
ip_addr_t server_ip;
struct netconn *conn = NULL;
struct netbuf *inBuf = NULL;
struct pbuf *q;
char *request = NULL;
uint16_t recvPos = 0;
uint8_t *recvBuf;
err_t err_msg;
while(gnetif.ip_addr.addr == 0x00)
{
return HTTP_ROUTE_NOT_FOUND;
}
if(strncmp((const char *)url, "http://", 7) == 0) /* 只处理http协议 */
{
server_addr = pvPortMalloc(strlen(url) - 7);
if(server_addr == NULL) return HTTP_OUT_OF_RAM;
/* 1)提取服务器部分 */
for(i = 4; url[i]; ++i)
{
if (url[i] == ':' && url[i + 1] == '/' && url[i + 2] == '/')
{
for (i = i + 3, j = 0; url[i] > 32 && url[i] < 127 && url[i] != '/';
++i, ++j)
{
server_addr[j] = url[i];
if (url[i] == '@') /* 服务器基础认证符号,我们做不了,遇到就错误. */
{
return HTTP_AUTH_NOT_SUPPORT;
}
}
server_addr[j] = ' ';
web_addr = pvPortMalloc(strlen(url) - 7 - strlen(server_addr));
if(web_addr == NULL) return HTTP_OUT_OF_RAM;
for (k = 7 + j; k < (strlen(url)); k++) /* 后半部分提取 */
{
web_addr[k - 7 - j] = url[k];
}
web_addr[k - 7 - j] = ' ';
while (--j)
{
if (server_addr[j] == ':')
{
server_addr[j] = ' ';
}
}
}
}
if(strlen(server_addr) < 2) /* 最短网址3.cn */
{
vPortFree(server_addr);
if(web_addr == NULL) vPortFree(web_addr); /* 这么短,还不一定提取到了这个. */
return HTTP_SERVER_ADDR_ERROR;
}
/* 2)查询IP */
netconn_gethostbyname(server_addr, &server_ip);
/* 3)构造访问头 */
request = pvPortMalloc(strlen(url) + 1024); /* 头所需内存大小. */
if(request == NULL) return HTTP_OUT_OF_RAM;
if(post != NULL)
sprintf(request, "POST %s HTTP/1.0
Host: %s
User-Agent: Mozilla/5.0 (lwip;STM32) TaterLi
Content-Length: %d
Content-Type: application/x-www-form-urlencoded
%s", web_addr, server_addr, strlen(post), post);
else
sprintf(request, "GET %s HTTP/1.0
Host: %s
User-Agent: Mozilla/5.0 (lwip;STM32) TaterLi
", web_addr, server_addr);
vPortFree(server_addr);
if(web_addr != NULL)
{
/* 万一没提取到,就是NULL,如果是NULL,那么也不用继续了. */
vPortFree(web_addr);
}
else
{
vPortFree(request);
return HTTP_NOT_VALID_ADDR;
}
/* 4)开始访问 */
conn = netconn_new(NETCONN_TCP);
err_msg = netconn_connect(conn, &server_ip, 80); /* 目前也只能支持80端口,比较常用,不考虑特殊情况. */
if (err_msg == ERR_OK)
{
netconn_write(conn, request, strlen((char *)request), NETCONN_COPY);
vPortFree(request);
conn->recv_timeout = 3000;
recvPos = 0;
if((err_msg = netconn_recv(conn, &inBuf)) == ERR_OK) /* HTTP 1.0 天然不拆包 */
{
recvBuf = pvPortMalloc(inBuf->p->tot_len);
if(recvBuf == NULL)
{
return HTTP_OUT_OF_RAM;
}
for(q = inBuf->p; q != NULL; q = q->next) //遍历完整个pbuf链表
{
memcpy(recvBuf + recvPos, q->payload, q->len);
recvPos += q->len;
}
}
netconn_close(conn);
netconn_delete(conn);
netbuf_delete(inBuf);
if(err_msg != ERR_OK) return HTTP_OUT_OF_RAM;
/* 5)分析数据(分析HTTP头,暂时不打算支持301之类的) */
for(i = 0; recvBuf[i]; ++i)
{
if (recvBuf[i] == '2' && recvBuf[i + 1] == '0' && recvBuf[i + 2] == '0')
{
/* 证明200 OK */
for(; recvBuf[i]; ++i)
{
/* 响应头的结束也是两个回车 */
if(recvBuf[i] == '
' && recvBuf[i + 1] == '
' && recvBuf[i + 2] == '
' && recvBuf[i + 3] == '
')
{
/* 6)复制正文内容 */
i += 4;
k = strlen((const char *)recvBuf) - i;
if(k == 0) return HTTP_NO_CONTENT;
*pageBuf = pvPortMalloc(k);
if(*pageBuf == NULL)
{
vPortFree(recvBuf);
return HTTP_OUT_OF_RAM;
}
memcpy((char *)*pageBuf, (const char *)recvBuf + i, k); /* 用HTTP1.0是没http chunked response的.方便处理,否则还要分段接收网页,大的网页反正MCU也接不下. */
vPortFree(recvBuf);
return HTTP_OK;
}
}
}
}
if(recvBuf != NULL) vPortFree(recvBuf);
return HTTP_NOT_200OK;
}
else
{
return HTTP_SERVER_REFUSE;
}
}
else
{
return HTTPS_NOT_SUPPORT;
}
}