Add XML parsing

src/feader.c

@@ -1,28 +1,81 @@
 #include "curl/curl.h"
 #include "curl/easy.h"
+#include "libxml/parser.h"
+#include "libxml/tree.h"
+#include "libxml/xmlreader.h"
+#include "libxml/xmlstring.h"
 #include <stdlib.h>
 #include <string.h>
 
 typedef struct {
     char* data;
     int size;
+    char* url;
+    char* errBuf;
 } xml;
 
 size_t my_write_callback(char *ptr, size_t size, size_t nmemb, xml *x);
 
 size_t get_xml(xml *x, char *url);
 
-int main(int argc, char **argv) {
+void parse_xml_items(xml *x, xmlDocPtr *doc);
+
 xml x;
+
+xmlDocPtr xdp;
+
+int main(int argc, char **argv) {
+    if (argc < 2) {
+        printf("Please provide the URL of a feed to parse.\n");
+        return 1;
+    } else {
+        printf("Attempting to retrieve XML for URL: %s\n", argv[1]);
+    }
     x.size = 0;
     x.data = malloc(1);
     x.data[0] = '\0';
+    x.url = argv[1];
+
+    int res = get_xml(&x, x.url);
+    // printf("\n%s\n", x.data);            
+    if (res == CURLE_OK) {
+        printf("XML data retrieved from server\n");
+    } else {
+        printf("Unable to retrieve XML for URL: %s\n", x.url);
+        printf("%s\n", x.errBuf);
+    }
+
+    parse_xml_items(&x, &xdp);
+
+    if (xdp == NULL || xdp->children == NULL) {
+        printf("Unable to parse XML\n");
+    }
+
+    xmlNode* rss = xdp->children;
+    xmlNode* channel = rss->children->next;
+    xmlNode* channelChild = channel->children;
+    int articleCount = 0;
+    while (channelChild != NULL) {
+        if (strncmp("title", channelChild->name, strlen(channelChild->name)) == 0) {
+            if (channelChild->children != NULL) {
+                printf("%s: %s\n", channelChild->name, channelChild->children->content);
+            }
+        } else if (strncmp("description", channelChild->name, strlen(channelChild->name)) == 0) {
+            if (channelChild->children != NULL) {
+                printf("%s: %s\n", channelChild->name, channelChild->children->content);
+            }
+        } else if (strncmp("item", channelChild->name, strlen(channelChild->name)) == 0) {
+            articleCount++;
+        }
+        channelChild = channelChild->next;
+    }
+
+    printf("Found %d articles in the feed\n", articleCount);
 
-    int res = get_xml(&x, "http://127.0.0.1/wbrawner-jekyll/_site/feed.xml");
 
-    printf("\n%s\n", x.data);
     free(x.data);
-    return res;
+    free(xdp);
+    return 0;
 }
 
 size_t my_write_callback(char *ptr, size_t size, size_t nmemb, xml *x) {
@@ -48,7 +101,20 @@ size_t get_xml(xml* x, char* url) {
     curl_easy_setopt(curl, CURLOPT_URL, url);
     curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, *my_write_callback);
     curl_easy_setopt(curl, CURLOPT_WRITEDATA, x);
+    curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, x->errBuf);
     CURLcode res = curl_easy_perform(curl);
     curl_easy_cleanup(curl);
     return res;
 }
+
+void parse_xml_items(xml *x, xmlDocPtr *doc) {
+    xmlChar* xChar = malloc(x->size);
+    xChar = xmlCharStrndup(x->data, x->size);
+    (*doc) = xmlReadDoc(
+            xChar,
+            x->url,
+            NULL,
+            XML_PARSE_RECOVER
+            );
+    free(xChar);
+}