httpc

httpc.c (3868B)

// SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+httpc@hacktivis.me>
// SPDX-License-Identifier: MPL-2.0
#define _POSIX_C_SOURCE 200809L
#include <limits.h> // PAGESIZE
#include <tls.h>
#include <errno.h>
#include <stdio.h> // fprintf
#include <unistd.h> // write, fsync
#include <string.h> // strlen, strerror
#include <stdlib.h> // abort
#include <stdbool.h>
#include <fcntl.h> // open, O_*
#include "httpc.h"
int body = 0;
bool verbose = false;
static size_t
read_header(const char *res, ssize_t len)
{
	size_t header_len = 0;
	for(ssize_t i = 0; i<len; i++)
	{
		if(res[i] == '\r' && res[i+1] == '\n') i++;
		if(res[i] == '\n')
		{
			if(header_len == 0)
			{
				body = 1;
				return i+1;
			}
			if(verbose)
			{
				fputs("> ", stderr);
				fwrite(res, 1, header_len, stderr);
				fputs("\n", stderr);
			}
			return i+1;
		}
		header_len++;
	}
	// Maybe case where first packet didn't contain all headers should be handled
	// But who the heck even sends >PAGESIZE of headers
	abort();
}
int
main(int argc, char *argv[])
{
	int out_flags = O_WRONLY | O_CLOEXEC | O_CREAT | O_NOCTTY | O_TRUNC;
	char *out_name = NULL;
	int out = -1;
	int c = -1;
	while((c = getopt(argc, argv, ":o:v")) != -1)
	{
		switch(c)
		{
		case 'o':
			out_name = optarg;
			break;
		case 'v':
			verbose = true;
			break;
		}
	}
	argv += optind;
	argc -= optind;
	// FIXME: URL basename
	if(out_name == NULL) out_name = "body";
	out = open(out_name, out_flags, 0644);
	if(out < 0)
	{
		fprintf(stderr, "httpc: Failed opening destination file '%s': %s\n", out_name, strerror(errno));
		return 1;
	}
	if(argc != 1)
	{
		fprintf(stderr, "httpc: Expected 1 argument, got %d\n", argc);
		return 1;
	}
	char *errstr = NULL;
	struct URI *uri = decode_uri(argv[0], &errstr);
	if(uri == NULL)
	{
		fprintf(stderr, "httpc: Error while decoding <%s>: %s\n", argv[0], errstr);
		return 1;
	}
	struct tls *tls_ctx = tls_client();
	struct tls_config *tls_cfg = tls_config_new();
	if(tls_configure(tls_ctx, tls_cfg) != 0)
	{
		fprintf(stderr, "httpc: TLS Configuration Error: %s\n", tls_error(tls_ctx));
		decode_uri_finish(uri);
		tls_config_free(tls_cfg);
		return 1;
	}
	if(tls_connect(tls_ctx, uri->host, uri->port ? uri->port : "443") != 0)
	{
		fprintf(stderr, "httpc: TLS Connection Error: %s\n", tls_error(tls_ctx));
		decode_uri_finish(uri);
		tls_config_free(tls_cfg);
		return 1;
	}
	int err = 0;
	if(tls_handshake(tls_ctx) != 0)
	{
		fprintf(stderr, "httpc: TLS Handshake Error: %s\n", tls_error(tls_ctx));
		err = 1;
		goto cleanup;
	}
	static const char *req_fmt = "\
GET %s HTTP/1.0\r\n\
Host: %s\r\n\
User-Agent: httpc/0.0\r\n\
Connection: close\r\n\
\r\n";
	char req[PAGESIZE];
	snprintf(req, PAGESIZE, req_fmt, uri->path ? uri->path : "/", uri->host);
	if(verbose) write(STDERR_FILENO, req, strlen(req));
	ssize_t nwrite = tls_write(tls_ctx, req, strlen(req));
	if(nwrite < 0)
	{
		fprintf(stderr, "httpc: Write Error: %s\n", tls_error(tls_ctx));
		err = 1;
		goto cleanup;
	}
	char res[PAGESIZE] = {};
	while(1)
	{
		ssize_t nread = tls_read(tls_ctx, res, PAGESIZE);
		if(nread == TLS_WANT_POLLIN || nread == TLS_WANT_POLLOUT)
			continue;
		if(nread < 0)
		{
			fprintf(stderr, "httpc: Write Error: %s\n", tls_error(tls_ctx));
			break;
		}
		if(nread == 0) break;
		ssize_t off = 0;
		// TODO: Read status
		while(body == 0 && off < nread) off += read_header(res+off, nread);
		if(body == 1) write(out, res+off, nread-off);
	}
	if(fsync(out) < 0)
	{
		fprintf(stderr, "httpc: Failed syncing destination file '%s' to disk: %s\n", out_name, strerror(errno));
		err = 1;
	}
	if(close(out) < 0)
	{
		fprintf(stderr, "httpc: Failed closing destination file '%s': %s\n", out_name, strerror(errno));
		err = 1;
	}
cleanup:
	decode_uri_finish(uri);
	tls_close(tls_ctx);
	tls_free(tls_ctx);
	tls_config_free(tls_cfg);
	return err;
}