small input downloader

Author: simonschnake

.gitignore

@@ -1,3 +1,4 @@
 inputs/
 .vscode/
 .DS_Store
+get_input

get_input.c

@@ -0,0 +1,89 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <curl/curl.h>
+
+// Replace with your session cookie value
+#define BASE_URL "https://adventofcode.com/2024/day/%d/input"
+
+// Callback function to write data to a file
+size_t write_data(void *ptr, size_t size, size_t nmemb, FILE *stream) {
+    size_t written = fwrite(ptr, size, nmemb, stream);
+    return written;
+}
+
+int main(int argc, char *argv[]) {
+    if (argc != 3) {
+        fprintf(stderr, "Usage: %s <session_cookie> <day>\n", argv[0]);
+        return 1;
+    }
+
+    // Parse command line arguments
+    int day = atoi(argv[2]);
+    if (day < 1 || day > 25) {
+        fprintf(stderr, "Invalid day\n");
+        return 1;
+    }
+
+    char *session_cookie = argv[1];
+
+    CURL *curl;
+    CURLcode res;
+
+    // Prepare the URL
+    char url[256];
+    snprintf(url, sizeof(url), BASE_URL, day); 
+
+    // Prepare the file path
+    char file_path[256];
+    snprintf(file_path, sizeof(file_path), "inputs/day%d", day);
+
+    // Create the "inputs" directory if it doesn't exist
+    if (system("mkdir -p inputs") != 0) {
+        perror("Error creating directory");
+        return 1;
+    }
+
+    FILE *fp = fopen(file_path, "wb");
+    if (!fp) {
+        perror("Error opening file");
+        return 1;
+    }
+
+    // Initialize CURL
+    curl = curl_easy_init();
+    if (curl) {
+        // Set URL
+        curl_easy_setopt(curl, CURLOPT_URL, url);
+
+        // Set the session cookie in the header
+        struct curl_slist *headers = NULL;
+        char cookie_header[512];
+        snprintf(cookie_header, sizeof(cookie_header), "Cookie: session=%s", session_cookie);
+        headers = curl_slist_append(headers, cookie_header);
+        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
+
+        // Set the User-Agent (optional but recommended)
+        curl_easy_setopt(curl, CURLOPT_USERAGENT, "C program for Advent of Code input");
+
+        // Write data to the file
+        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
+        curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
+
+        // Perform the request
+        res = curl_easy_perform(curl);
+        if (res != CURLE_OK) {
+            fprintf(stderr, "CURL error: %s\n", curl_easy_strerror(res));
+        } else {
+            printf("Input for day %d successfully saved to %s\n", day, file_path);
+        }
+
+        // Clean up
+        curl_easy_cleanup(curl);
+        curl_slist_free_all(headers);
+    } else {
+        fprintf(stderr, "Error initializing CURL\n");
+    }
+
+    fclose(fp);
+    return 0;
+}