Initial commit

http.c

@@ -0,0 +1,208 @@
+#include <curl/curl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include "http.h"
+
+static char* strnstrr(const char *str, const char *needle, size_t size) {
+
+	char *ptr;
+	size_t len, pos;
+
+	if (!needle || !*needle)
+		return (char *) str;
+
+	len = strlen(needle);
+	pos = size;
+	for(ptr=(char*)str; *ptr; ptr = memchr(ptr+1, *needle, pos-1)) {
+		pos = size - (ptr - str);
+		if (pos < len)
+			break;
+		if (!strncmp(ptr, needle, len))
+			return ptr + len;
+	}
+	return NULL;
+}
+
+static char* url_filename(const char *url) {
+
+	const char *start = url;
+	char *name = NULL;
+	size_t size;
+
+	for(; *url; url++) {
+		if (*url != '/')
+			continue;
+		if (*(url+1)) {
+			start = url+1;
+		} else {
+			url--;
+			break;
+		}
+	}
+	size = url - start;
+	if (size) {
+		name = malloc(size + 1);
+		memcpy(name, start, size + 1);
+		name[size+1] = '\0';
+	}
+	return name;
+}
+
+#define HDR_CONDISP "Content-Disposition:"
+
+static size_t hdr_fname_cb(void *src, size_t smemb, size_t nmemb, void *data) {
+
+	int pos, size = smemb * nmemb;
+	char *ptr = (char *) src;
+	char **filename = (char**) data;
+
+	if (*filename || size < sizeof(HDR_CONDISP)-1 ||
+		memcmp(ptr, HDR_CONDISP, sizeof(HDR_CONDISP)-1))
+		return size;
+
+	pos = sizeof(HDR_CONDISP)-1;
+	ptr = strnstrr(ptr + pos, "filename=\"", size);
+	if (ptr) {
+		int start, len;
+		start = pos = ptr - ((char*) src);
+		ptr = (char *) src;
+		for(len=0;;len++) {
+			if (ptr[pos] == '"' && ptr[pos-1] != '\\')
+				break;
+			if (++pos > size)
+				return 0;
+		}
+		if (len)
+			*filename = strndup(ptr + start, len);
+	}
+	return size;
+}
+
+static size_t write_cb(void *src, size_t smemb, size_t nmemb, void *data) {
+
+	struct http_data *dest = (struct http_data *) data;
+	size_t size = smemb * nmemb;
+
+	dest->block = realloc(dest->block, dest->len + size);
+	if (dest->block == NULL) {
+		printf("out of memory\n");
+		return 0;
+	}
+	memcpy(dest->block + dest->len, src, size);
+	dest->len += size;
+
+	return size;
+}
+
+static CURL* setup_connection(const char *url) {
+
+	CURL *handle = curl_easy_init();
+
+	curl_easy_setopt(handle, CURLOPT_URL, url);
+	curl_easy_setopt(handle, CURLOPT_USERAGENT, "libcurl-agent/1.0");
+	curl_easy_setopt(handle, CURLOPT_SSL_VERIFYHOST, 0);
+	curl_easy_setopt(handle, CURLOPT_SSL_VERIFYPEER, 0);
+	curl_easy_setopt(handle, CURLOPT_TIMEOUT, 10);
+
+	return handle;
+}
+
+struct http_data* http_fetch_page(const char *url) {
+
+	CURL *handle = curl_easy_init();
+	CURLcode res;
+	struct http_data *data = malloc(sizeof(struct http_data));
+
+	data->block = NULL;
+	data->len = 0;
+
+	handle = setup_connection(url);
+
+	curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, write_cb);
+	curl_easy_setopt(handle, CURLOPT_WRITEDATA, data);
+
+	res = curl_easy_perform(handle);
+
+	if (res != CURLE_OK) {
+		printf("curl: (%s) %s\n", url, curl_easy_strerror(res));
+		goto error;
+	}
+
+	curl_easy_cleanup(handle);
+
+	return data;
+error:
+	curl_easy_cleanup(handle);
+	http_free(data);
+	return NULL;
+}
+
+int http_download_file(const char *url, const char *dir) {
+
+	int fd, err;
+	char *filename = NULL;
+	char path[4096];
+	CURL *handle;
+	CURLcode res;
+	struct http_data *data = malloc(sizeof(struct http_data));
+
+	data->block = NULL;
+	data->len = 0;
+
+	handle = setup_connection(url);
+
+	curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, write_cb);
+	curl_easy_setopt(handle, CURLOPT_WRITEDATA, data);
+
+	curl_easy_setopt(handle, CURLOPT_HEADERFUNCTION, hdr_fname_cb);
+	curl_easy_setopt(handle, CURLOPT_HEADERDATA, &filename);
+
+	res = curl_easy_perform(handle);
+
+	if (res != CURLE_OK) {
+		printf("curl: (%s) %s\n", url, curl_easy_strerror(res));
+		goto error;
+	}
+
+	if (!filename) {
+		filename = url_filename(url);
+	}
+
+	/* now, write to file */
+	snprintf(path, sizeof(path), "%s/%s", dir, filename);
+	fd = open(path, O_CREAT | O_EXCL | O_WRONLY, 0644);
+	if (fd < 0)
+		goto error;
+
+	write(fd, data->block, data->len);
+
+	close(fd);
+
+	free(filename);
+	http_free(data);
+	curl_easy_cleanup(handle);
+
+	return 0;
+error:
+	err = errno;
+	if (filename)
+		free(filename);
+	http_free(data);
+	curl_easy_cleanup(handle);
+	errno = err;
+	return -1;
+}
+
+void http_free(struct http_data *data) {
+
+	if (!data)
+		return;
+	if (data->block)
+		free(data->block);
+	free(data);
+}