httpc

uri.c (3320B)

// SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+httpc@hacktivis.me>
// SPDX-License-Identifier: MPL-2.0
#define _POSIX_C_SOURCE 200809L
#include "httpc.h"
#include <assert.h>
#include <errno.h>
#include <ctype.h> // isalnum, iscntrl
#include <string.h> // strlen, strerror, strdup
#include <stdlib.h> // free
// rfc1945.html#section-3.2
static inline int
is_reserved(int c)
{
	return c == ';' || c == '/' || c == '?' || c == ':' || c == '@' || c == '&' | c == '=' | c == '+';
}
static inline int
is_extra(int c)
{
	return c == '!' || c == '*' || c == '\'' || c == '(' || c == ')' || c == ',';
}
static inline int
is_safe(int c)
{
	return c == '$' || c == '-' || c == '_' || c == '.';
}
static inline int
is_unsafe(int c)
{
	return iscntrl(c) || c == ' ' || c == '#' || c == '%' || c == '<' || c == '>';
}
static int
is_national(int c)
{
	return !isalnum(c) && !is_reserved(c) && !is_extra(c) && !is_safe(c) && !is_unsafe(c);
}
static int
is_unreserved(int c)
{
	return isalnum(c) || is_safe(c) || is_extra(c) || is_national(c);
}
void
decode_uri_finish(struct URI *uri)
{
	if(uri == NULL) return;
	free(uri->scheme);
	free(uri->host);
	if(uri->port != NULL) free(uri->port);
}
// Caller must call decode_uri_finish
struct URI *
decode_uri(const char *ori, char **err)
{
	static struct URI uri = {
		.scheme = NULL,
		.host = NULL,
		.port = NULL,
		.path = NULL,
		.fragment = NULL
	};
	if(ori == NULL)
	{
		*err = "Null pointer passed";
		return NULL;
	}
	errno = 0;
	char *arg = strdup(ori);
	if(arg == NULL)
	{
		*err = strerror(errno);
		return NULL;
	}
	int i = 0;
	int len = strlen(arg);
	// scheme
	for(;i<len;i++)
	{
		char c = arg[i];
		if(isalnum(c) || c == '+' || c == '-' || c == '.') continue;
		if(c != ':')
		{
			static char error[] = "Invalid char in scheme: _";
			error[sizeof(error)-2] = c;
			*err = error;
			free(arg);
			return NULL;
		}
		arg[i++] = '\0';
		uri.scheme = arg;
		break;
	}
	if(arg[i] != '/' || arg[i+1] != '/')
	{
		*err = "Missing :// after scheme";
		free(arg);
		return NULL;
	} else i+=2;
	// IPv6 address
	if(arg[i] == '[')
	{
		char *addr = arg+i+1;
		for(;i<len && arg[i] != ']';i++);
		if(arg[i] != ']')
		{
			*err = "Unmatched [ in host";
			free(arg);
			return NULL;
		};
		arg[i] = '\0';
		i++;
		uri.host = strdup(addr);
		if(uri.host == NULL)
		{
			*err = "host = strdup(...) failed";
			free(arg);
			return NULL;
		}
	}
	else
	{
		char *addr = arg+i;
		size_t addr_len = 0;
		// hostname or IPv4 address
		for(;i<len;i++,addr_len++)
		{
			char c = arg[i];
			if(c == '/' || c == ':') break;
		}
		uri.host = strndup(addr, addr_len);
		if(uri.host == NULL)
		{
			*err = "host = strdup(...) failed";
			free(arg);
			return NULL;
		}
	}
	// port (optional)
	if(arg[i] == ':')
	{
		arg[i++] = '\0';
		char *port = arg+i;
		size_t port_len = 0;
		for(;i<len;i++,port_len++)
		{
			char c = arg[i];
			if(c == '/') break;
			if(!isdigit(c))
			{
				static char error[] = "Invalid char in port: _";
				error[sizeof(error)-2] = c;
				*err = error;
				free(arg);
				return NULL;
			}
		}
		uri.port = strndup(port, port_len);
		if(uri.port == NULL)
		{
			*err = "port = strdup(...) failed";
			free(arg);
			return NULL;
		}
	}
	// FIXME: Check for invalid characters
	uri.path = arg+i;
	return &uri;
}