UPnP implementation

Service type
urn:schemas-upnp-org:service:ContentDirectory:1

Action name
GetSystemUpdateID

HTTP header

SOAPACTION: "urn:schemas-upnp-org:service:ContentDirectory:1#GetSystemUpdateID"

XML

<?xml version="1.0" encoding="UTF-8"?>
<s:Envelope s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">

<s:Body>

<u:GetSystemUpdateID xmlns:u="urn:schemas-upnp-org:service:ContentDirectory:1"/>

</s:Body>

</s:Envelope>

SOAP response 예

HTTP header
HTTP/1.1 200 OK
CONTENT-TYPE: text/xml; charset="utf-8"
EXT:
SERVER: UPnP/1.0 DLNADOC/1.50 Platinum/1.0.5.13
Content-Length: 328

XML
<?xml version="1.0" encoding="UTF-8"?>
<s:Envelope s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
<s:Body>
<u:GetSystemUpdateIDResponse xmlns:u="urn:schemas-upnp-org:service:ContentDirectory:1">
<Id>76941487</Id>
</u:GetSystemUpdateIDResponse>
</s:Body>
</s:Envelope>

2018년 4월 27일 금요일

uuid - C언어

UUID

설치

$ sudo apt install uuid-dev

sample code

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <uuid/uuid.h>

int main(int argc, char *argv[])
{
    char uuid_str[37];
    uuid_t uuid;
    uuid_generate_time_safe(uuid);
    uuid_unparse_lower(uuid, uuid_str);
    printf("uuid: %s\n", uuid_str);

    return 0;
}

Build

$ gcc -o gen main.c `pkg-config --cflags --libs uuid`

실행

$ ./gen
uuid: 1b4e28ba-2fa1-11d2-883f-0016d3cca427

xml - libxml

http://xmlsoft.org/

설치

$ sudo apt install libxml2-dev

sample code

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libxml/parser.h>

static void s_print_attributes(xmlNode * node)
{
    xmlAttr * props = node->properties;
    xmlNode * attr;
    if (props == NULL) {
        return;
    }
    printf("{");
    for (; props; props = props->next) {
        if (props->prev) {
            printf(" ");
        }
        printf("%s: %s", props->name, props->xmlChildrenNode->content);
    }
    printf("}");
}

static void s_print_first_child(xmlNode * node, const char * prefix)
{
    xmlNode * first = node->xmlChildrenNode;
    if (!first || first->next) {
        return;
    }

    printf("%s", prefix);
    printf("Content: '%s'\n", first->content);
}

static void s_print_child_elements(xmlNode * node, const char * prefix)
{
    xmlNode * child;
    for (child = node->xmlChildrenNode; child; child = child->next) {
        if (child->type == XML_ELEMENT_NODE) {
            char prefix_[10] = {0,};
            snprintf(prefix_, sizeof(prefix_), " %s", prefix);
            printf("%s", prefix);
            printf("Name: %s ", child->name);
            s_print_attributes(child);
            printf("\n");
            s_print_first_child(child, prefix_);
            s_print_child_elements(child, prefix_);
        }
    }
}

int main(int argc, char *argv[])
{
    LIBXML_TEST_VERSION
    xmlDoc * doc;
    xmlNode * root;
    xmlNode * cur_node = NULL;

    if (argc < 2) {
        fprintf(stderr, "usage: %s <xml path>\n", argv[0]);
        exit(1);
    }

    doc = xmlReadFile(argv[1], NULL, 0);
    if (doc == NULL) {
        fprintf(stderr, "xmlReadFile() failed\n");
        exit(1);
    }

    root = xmlDocGetRootElement(doc);
    s_print_child_elements(root, "");

    xmlFreeDoc(doc);
    xmlCleanupParser();
    xmlMemoryDump();
    return 0;
}

빌드

$ gcc -o parse main.c `pkg-config --cflags --libs libxml-2.0`

light.xml

<?xml version="1.0"?>
<root xmlns="urn:schemas-upnp-org:device-1-0">
<specVersion>
    <major>1</major>
    <minor>0</minor>
</specVersion>
<device>
    <deviceType>urn:schemas-upnp-org:device:BinaryLight:0.9</deviceType>
    <friendlyName>Living Room</friendlyName>
    <manufacturer>My company</manufacturer>
    <manufacturerURL>URL to manufacturer site</manufacturerURL>
    <modelDescription>Remote Light Control</modelDescription>
    <modelName>Light</modelName>
    <modelNumber>0001</modelNumber>
    <modelURL>URL to model site</modelURL>
    <serialNumber>SN0001</serialNumber>
    <UDN>uuid:UUID</UDN>
    <serviceList>
      <service>
        <serviceType>urn:schemas-upnp-org:service:SwitchPower:1</serviceType>
        <serviceId>urn:upnp-org:serviceId:SwitchPower:1</serviceId>
        <SCPDURL>/switchpower.xml</SCPDURL>
        <controlURL>URL for control</controlURL>
        <eventSubURL>URL for eventing</eventSubURL>
    </service>
    </serviceList>
</device>
</root>

실행

$ ./parse light.xml
Name: specVersion
Name: major
    Content: '1'
Name: minor
    Content: '0'
Name: device
Name: deviceType
    Content: 'urn:schemas-upnp-org:device:BinaryLight:0.9'
Name: friendlyName
    Content: 'Living Room'
Name: manufacturer
    Content: 'My company'
Name: manufacturerURL
    Content: 'URL to manufacturer site'
Name: modelDescription
    Content: 'Remote Light Control'
Name: modelName
    Content: 'Light'
Name: modelNumber
    Content: '0001'
Name: modelURL
    Content: 'URL to model site'
Name: serialNumber
    Content: 'SN0001'
Name: UDN
    Content: 'uuid:UUID'
Name: serviceList
    Name: service
      Name: serviceType
        Content: 'urn:schemas-upnp-org:service:SwitchPower:1'
      Name: serviceId
        Content: 'urn:upnp-org:serviceId:SwitchPower:1'
      Name: SCPDURL
        Content: '/switchpower.xml'
      Name: controlURL
        Content: 'URL for control'
      Name: eventSubURL
        Content: 'URL for eventing'

switchpower.xml

<?xml version="1.0"?>
<scpd xmlns="urn:schemas-upnp-org:service-1-0">
<specVersion>
    <major>1</major>
    <minor>0</minor>
</specVersion>
<actionList>
    <action>
    <name>SetTarget</name>
    <argumentList>
        <argument>
        <name>newTargetValue</name>
        <relatedStateVariable>Target</relatedStateVariable>
        <direction>in</direction>
        </argument>
    </argumentList>
    </action>
    <action>
    <name>GetTarget</name>
    <argumentList>
        <argument>
        <name>RetTargetValue</name>
        <relatedStateVariable>Target</relatedStateVariable>
        <direction>out</direction>
        </argument>
    </argumentList>
    </action>
    <action>
    <name>GetStatus</name>
    <argumentList>
        <argument>
        <name>ResultStatus</name>
        <relatedStateVariable>Status</relatedStateVariable>
        <direction>out</direction>
        </argument>
    </argumentList>
    </action>
</actionList>
<serviceStateTable>
    <stateVariable sendEvents="no">
    <name>Target</name>
    <dataType>boolean</dataType>
    <defaultValue>0</defaultValue>
    </stateVariable>
    <stateVariable sendEvents="yes">
    <name>Status</name>
    <dataType>boolean</dataType>
    <defaultValue>0</defaultValue>
    </stateVariable>
</serviceStateTable>
</scpd>

실행

$ ./parse switchpower.xml
Name: specVersion
Name: major
    Content: '1'
Name: minor
    Content: '0'
Name: actionList
Name: action
    Name: name
      Content: 'SetTarget'
    Name: argumentList
      Name: argument
        Name: name
         Content: 'newTargetValue'
        Name: relatedStateVariable
         Content: 'Target'
        Name: direction
         Content: 'in'
Name: action
    Name: name
      Content: 'GetTarget'
    Name: argumentList
      Name: argument
        Name: name
         Content: 'RetTargetValue'
        Name: relatedStateVariable
         Content: 'Target'
        Name: direction
         Content: 'out'
Name: action
    Name: name
      Content: 'GetStatus'
    Name: argumentList
      Name: argument
        Name: name
         Content: 'ResultStatus'
        Name: relatedStateVariable
         Content: 'Status'
        Name: direction
         Content: 'out'
Name: serviceStateTable
Name: stateVariable {sendEvents: no}
    Name: name
      Content: 'Target'
    Name: dataType
      Content: 'boolean'
    Name: defaultValue
      Content: '0'
Name: stateVariable {sendEvents: yes}
    Name: name
      Content: 'Status'
    Name: dataType
      Content: 'boolean'
    Name: defaultValue
      Content: '0'

2018년 4월 23일 월요일

http client - libcurl

참고:

libcurl - https://curl.haxx.se/libcurl/
libcurl get - https://curl.haxx.se/libcurl/c/simple.html
libcurl post - https://curl.haxx.se/libcurl/c/post-callback.html
HTTP test server - https://httpbin.org/

Http get sample

http get
응답 데이터를 .out 파일로 저장

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curl/curl.h>

static size_t cb_write(void * contents, size_t size, size_t nmemb, void * userp)
{
    FILE * fp = (FILE*)userp;
    fwrite(contents, size, nmemb, fp);
    return size * nmemb;
}

static void dumpfile(const char * path);

int main(int argc, char *argv[])
{
    FILE * out;
    CURLcode res;
    CURL * curl;

    curl_global_init(CURL_GLOBAL_ALL);

    curl = curl_easy_init();
    if (!curl) {
        printf("curl_easy_init() failed\n");
        exit(1);
    }

    out = fopen(".out", "wb");
    if (!out) {
        printf("fopen() failed\n");
        exit(1);
    }

    curl_easy_setopt(curl, CURLOPT_URL, "http://httpbin.org/get");
    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, cb_write);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void*)out);
    res = curl_easy_perform(curl);
    if (res != CURLE_OK) {
        fclose(out);
        printf("curl_easy_perform() failed\n");
        exit(1);
    }
    fclose(out);

    dumpfile(".out");

    curl_easy_cleanup(curl);

    curl_global_cleanup();

    return 0;
}

static void dumpfile(const char * path) {
    int len;
    char buf[1024] = {0,};
    FILE * fp = fopen(path, "rb");
    if (!fp) {
        perror("fopen() failed");
        exit(1);
    }

    while ((len = fread(buf, sizeof(char), sizeof(buf), fp)) > 0) {
        printf("%.*s", len, buf);
    }

    fclose(fp);
}

빌드

$ gcc -o httpget main.c `pkg-config --cflags --libs libcurl`

실행

$ ./httpget
{
"args": {},
"headers": {
    "Accept": "*/*",
    "Connection": "close",
    "Host": "httpbin.org"
},
"origin": "xx.xx.xx.xx",
"url": "http://httpbin.org/get"
}

Http post sample

http post
Content-Type: text/plain

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curl/curl.h>

static size_t cb_write(void * contents, size_t size, size_t nmemb, void * userp)
{
    FILE * fp = (FILE*)userp;
    fwrite(contents, size, nmemb, fp);
    return size * nmemb;
}

static void dumpfile(const char * path);

int main(int argc, char *argv[])
{
    struct curl_slist * headers = NULL;
    static const char * msg = "hello world";
    FILE * out;
    CURLcode res;
    CURL * curl;

    curl_global_init(CURL_GLOBAL_ALL);

    curl = curl_easy_init();
    if (!curl) {
        printf("curl_easy_init() failed\n");
        exit(1);
    }

    out = fopen(".out", "wb");
    if (!out) {
        printf("fopen() failed\n");
        exit(1);
    }

    headers = curl_slist_append(headers, "Content-Type: text/plain");
    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

    curl_easy_setopt(curl, CURLOPT_URL, "http://httpbin.org/post");
    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
    curl_easy_setopt(curl, CURLOPT_POST, 1L);
    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, msg);
    curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, strlen(msg));
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, cb_write);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void*)out);
    res = curl_easy_perform(curl);
    curl_slist_free_all(headers);
    if (res != CURLE_OK) {
        fclose(out);
        fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
        exit(1);
    }
    fclose(out);
    dumpfile(".out");
    curl_easy_cleanup(curl);
    curl_global_cleanup();

    return 0;
}

static void dumpfile(const char * path) {
    int len;
    char buf[1024] = {0,};
    FILE * fp = fopen(path, "rb");
    if (!fp) {
        perror("fopen() failed");
        exit(1);
    }

    while ((len = fread(buf, sizeof(char), sizeof(buf), fp)) > 0) {
        printf("%.*s", len, buf);
    }

    fclose(fp);
}

빌드

$ gcc -o httppost main.c `pkg-config --cflags --libs libcurl`

실행

$ ./httppost
{
"args": {},
"data": "hello world",
"files": {},
"form": {},
"headers": {
    "Accept": "*/*",
    "Connection": "close",
    "Content-Length": "11",
    "Content-Type": "text/plain",
    "Host": "httpbin.org"
},
"json": null,
"origin": "xx.xx.xx.xx",
"url": "http://httpbin.org/post"
}

2018년 4월 22일 일요일

http server - microhttpd

micro http server

https://www.gnu.org/software/libmicrohttpd/

설치

$ brew install libmicrohttpd

sample code

#include <microhttpd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>

#define PAGE "<html><head><title>libmicrohttpd demo</title>"\
"</head><body>libmicrohttpd demo</body></html>"

static int ahc_echo(void * cls,
struct MHD_Connection * connection,
const char * url,
const char * method,
const char * version,
const char * upload_data,
size_t * upload_data_size,
void ** ptr) {
static int dummy;
const char * page = cls;
struct MHD_Response * response;
int ret;

if (0 != strcmp(method, "GET"))
return MHD_NO; /* unexpected method */
if (&dummy != *ptr)
{
/* The first time only the headers are valid,
do not respond in the first round... */
*ptr = &dummy;
return MHD_YES;
}
if (0 != *upload_data_size)
return MHD_NO; /* upload data in a GET!? */
*ptr = NULL; /* clear context pointer */
response = MHD_create_response_from_buffer (strlen(page),
(void*) page,
MHD_RESPMEM_PERSISTENT);
ret = MHD_queue_response(connection,
MHD_HTTP_OK,
response);
MHD_destroy_response(response);
return ret;
}

int main(int argc,
char ** argv) {
struct MHD_Daemon * d;
if (argc != 2) {
printf("%s PORT\n",
argv[0]);
return 1;
}
d = MHD_start_daemon(MHD_USE_THREAD_PER_CONNECTION,
atoi(argv[1]),
NULL,
NULL,
&ahc_echo,
PAGE,
MHD_OPTION_END);
if (d == NULL)
return 1;
(void) getc (stdin);
MHD_stop_daemon(d);
return 0;
}

빌드

$ gcc -o server main.c `pkg-config --cflags --libs libmicrohttpd`