CGDWebServer/GCDWebServerRequest.m

/*
 Copyright (c) 2012-2013, Pierre-Olivier Latour
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright
 notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright
 notice, this list of conditions and the following disclaimer in the
 documentation and/or other materials provided with the distribution.
 * The name of Pierre-Olivier Latour may not be used to endorse
 or promote products derived from this software without specific
 prior written permission.
 
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 DISCLAIMED. IN NO EVENT SHALL PIERRE-OLIVIER LATOUR BE LIABLE FOR ANY
 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#import "GCDWebServerPrivate.h"

#define kMultiPartBufferSize (256 * 1024)

enum {
  kParserState_Undefined = 0,
  kParserState_Start,
  kParserState_Headers,
  kParserState_Content,
  kParserState_End
};

static NSData* _newlineData = nil;
static NSData* _newlinesData = nil;
static NSData* _dashNewlineData = nil;

static NSString* _ExtractHeaderParameter(NSString* header, NSString* attribute) {
  NSString* value = nil;
  if (header) {
    NSScanner* scanner = [[NSScanner alloc] initWithString:header];
    NSString* string = [NSString stringWithFormat:@"%@=", attribute];
    if ([scanner scanUpToString:string intoString:NULL]) {
      [scanner scanString:string intoString:NULL];
      if ([scanner scanString:@"\"" intoString:NULL]) {
        [scanner scanUpToString:@"\"" intoString:&value];
      } else {
        [scanner scanUpToCharactersFromSet:[NSCharacterSet whitespaceCharacterSet] intoString:&value];
      }
    }
    [scanner release];
  }
  return value;
}

// http://www.w3schools.com/tags/ref_charactersets.asp
static NSStringEncoding _StringEncodingFromCharset(NSString* charset) {
  NSStringEncoding encoding = kCFStringEncodingInvalidId;
  if (charset) {
    encoding = CFStringConvertEncodingToNSStringEncoding(CFStringConvertIANACharSetNameToEncoding((CFStringRef)charset));
  }
  return (encoding != kCFStringEncodingInvalidId ? encoding : NSUTF8StringEncoding);
}

@implementation GCDWebServerRequest : NSObject

@synthesize method=_method, URL=_url, headers=_headers, path=_path, query=_query, contentType=_type, contentLength=_length;

- (id)initWithMethod:(NSString*)method url:(NSURL*)url headers:(NSDictionary*)headers path:(NSString*)path query:(NSDictionary*)query {
  if ((self = [super init])) {
    _method = [method copy];
    _url = [url retain];
    _headers = [headers retain];
    _path = [path copy];
    _query = [query retain];
    
    _type = [[_headers objectForKey:@"Content-Type"] retain];
    NSInteger length = [[_headers objectForKey:@"Content-Length"] integerValue];
    if (length < 0) {
      DNOT_REACHED();
      [self release];
      return nil;
    }
    _length = length;
    
    if ((_length > 0) && (_type == nil)) {
      _type = [kGCDWebServerDefaultMimeType copy];
    }
  }
  return self;
}

- (void)dealloc {
  [_method release];
  [_url release];
  [_headers release];
  [_path release];
  [_query release];
  [_type release];
  
  [super dealloc];
}

- (BOOL)hasBody {
  return _type ? YES : NO;
}

@end

@implementation GCDWebServerRequest (Subclassing)

- (BOOL)open {
  [self doesNotRecognizeSelector:_cmd];
  return NO;
}

- (NSInteger)write:(const void*)buffer maxLength:(NSUInteger)length {
  [self doesNotRecognizeSelector:_cmd];
  return -1;
}

- (BOOL)close {
  [self doesNotRecognizeSelector:_cmd];
  return NO;
}

@end

@implementation GCDWebServerDataRequest

@synthesize data=_data;

- (void)dealloc {
  DCHECK(_data != nil);
  [_data release];
  
  [super dealloc];
}

- (BOOL)open {
  DCHECK(_data == nil);
  _data = [[NSMutableData alloc] initWithCapacity:self.contentLength];
  return _data ? YES : NO;
}

- (NSInteger)write:(const void*)buffer maxLength:(NSUInteger)length {
  DCHECK(_data != nil);
  [_data appendBytes:buffer length:length];
  return length;
}

- (BOOL)close {
  DCHECK(_data != nil);
  return YES;
}

@end

@implementation GCDWebServerFileRequest

@synthesize filePath=_filePath;

- (id)initWithMethod:(NSString*)method url:(NSURL*)url headers:(NSDictionary*)headers path:(NSString*)path query:(NSDictionary*)query {
  if ((self = [super initWithMethod:method url:url headers:headers path:path query:query])) {
    _filePath = [[NSTemporaryDirectory() stringByAppendingPathComponent:[[NSProcessInfo processInfo] globallyUniqueString]] retain];
  }
  return self;
}

- (void)dealloc {
  DCHECK(_file < 0);
  unlink([_filePath fileSystemRepresentation]);
  [_filePath release];
  
  [super dealloc];
}

- (BOOL)open {
  DCHECK(_file == 0);
  _file = open([_filePath fileSystemRepresentation], O_CREAT | O_TRUNC | O_WRONLY, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
  return (_file > 0 ? YES : NO);
}

- (NSInteger)write:(const void*)buffer maxLength:(NSUInteger)length {
  DCHECK(_file > 0);
  return write(_file, buffer, length);
}

- (BOOL)close {
  DCHECK(_file > 0);
  int result = close(_file);
  _file = -1;
  return (result == 0 ? YES : NO);
}

@end

@implementation GCDWebServerURLEncodedFormRequest

@synthesize arguments=_arguments;

+ (NSString*)mimeType {
  return @"application/x-www-form-urlencoded";
}

- (void)dealloc {
  [_arguments release];
  
  [super dealloc];
}

- (BOOL)close {
  if (![super close]) {
    return NO;
  }
  
  NSString* charset = _ExtractHeaderParameter(self.contentType, @"charset");
  NSString* string = [[NSString alloc] initWithData:self.data encoding:_StringEncodingFromCharset(charset)];
  _arguments = [GCDWebServerParseURLEncodedForm(string) retain];
  [string release];
  
  return (_arguments ? YES : NO);
}

@end

@implementation GCDWebServerMultiPart

@synthesize contentType=_contentType, mimeType=_mimeType;

- (id)initWithContentType:(NSString*)contentType {
  if ((self = [super init])) {
    _contentType = [contentType copy];
    NSArray* components = [_contentType componentsSeparatedByString:@";"];
    if (components.count) {
      _mimeType = [[[components objectAtIndex:0] lowercaseString] retain];
    }
    if (_mimeType == nil) {
      _mimeType = @"text/plain";
    }
  }
  return self;
}

- (void)dealloc {
  [_contentType release];
  [_mimeType release];
  
  [super dealloc];
}

@end

@implementation GCDWebServerMultiPartArgument

@synthesize data=_data, string=_string;

- (id)initWithContentType:(NSString*)contentType data:(NSData*)data {
  if ((self = [super initWithContentType:contentType])) {
    _data = [data retain];
    
    if ([self.mimeType hasPrefix:@"text/"]) {
      NSString* charset = _ExtractHeaderParameter(self.contentType, @"charset");
      _string = [[NSString alloc] initWithData:_data encoding:_StringEncodingFromCharset(charset)];
    }
  }
  return self;
}

- (void)dealloc {
  [_data release];
  [_string release];
  
  [super dealloc];
}

- (NSString*)description {
  return [NSString stringWithFormat:@"<%@ | '%@' | %i bytes>", [self class], self.mimeType, (int)_data.length];
}

@end

@implementation GCDWebServerMultiPartFile

@synthesize fileName=_fileName, temporaryPath=_temporaryPath;

- (id)initWithContentType:(NSString*)contentType fileName:(NSString*)fileName temporaryPath:(NSString*)temporaryPath {
  if ((self = [super initWithContentType:contentType])) {
    _fileName = [fileName copy];
    _temporaryPath = [temporaryPath copy];
  }
  return self;
}

- (void)dealloc {
  unlink([_temporaryPath fileSystemRepresentation]);
  
  [_fileName release];
  [_temporaryPath release];
  
  [super dealloc];
}

- (NSString*)description {
  return [NSString stringWithFormat:@"<%@ | '%@' | '%@>'", [self class], self.mimeType, _fileName];
}

@end

@implementation GCDWebServerMultiPartFormRequest

@synthesize arguments=_arguments, files=_files;

+ (void)initialize {
  if (_newlineData == nil) {
    _newlineData = [[NSData alloc] initWithBytes:"\r\n" length:2];
    DCHECK(_newlineData);
  }
  if (_newlinesData == nil) {
    _newlinesData = [[NSData alloc] initWithBytes:"\r\n\r\n" length:4];
    DCHECK(_newlinesData);
  }
  if (_dashNewlineData == nil) {
    _dashNewlineData = [[NSData alloc] initWithBytes:"--\r\n" length:4];
    DCHECK(_dashNewlineData);
  }
}

+ (NSString*)mimeType {
  return @"multipart/form-data";
}

- (id)initWithMethod:(NSString*)method url:(NSURL*)url headers:(NSDictionary*)headers path:(NSString*)path query:(NSDictionary*)query {
  if ((self = [super initWithMethod:method url:url headers:headers path:path query:query])) {
    NSString* boundary = _ExtractHeaderParameter(self.contentType, @"boundary");
    if (boundary) {
      _boundary = [[[NSString stringWithFormat:@"--%@", boundary] dataUsingEncoding:NSASCIIStringEncoding] retain];
    }
    if (_boundary == nil) {
      DNOT_REACHED();
      [self release];
      return nil;
    }
    
    _arguments = [[NSMutableDictionary alloc] init];
    _files = [[NSMutableDictionary alloc] init];
  }
  return self;
}

- (BOOL)open {
  DCHECK(_parserData == nil);
  _parserData = [[NSMutableData alloc] initWithCapacity:kMultiPartBufferSize];
  _parserState = kParserState_Start;
  return YES;
}

// http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4
- (BOOL)_parseData {
  BOOL success = YES;
  
  if (_parserState == kParserState_Headers) {
    NSRange range = [_parserData rangeOfData:_newlinesData options:0 range:NSMakeRange(0, _parserData.length)];
    if (range.location != NSNotFound) {
      
      [_controlName release];
      _controlName = nil;
      [_fileName release];
      _fileName = nil;
      [_contentType release];
      _contentType = nil;
      [_tmpPath release];
      _tmpPath = nil;
      CFHTTPMessageRef message = CFHTTPMessageCreateEmpty(kCFAllocatorDefault, true);
      const char* temp = "GET / HTTP/1.0\r\n";
      CFHTTPMessageAppendBytes(message, (const UInt8*)temp, strlen(temp));
      CFHTTPMessageAppendBytes(message, _parserData.bytes, range.location + range.length);
      if (CFHTTPMessageIsHeaderComplete(message)) {
        NSString* controlName = nil;
        NSString* fileName = nil;
        NSDictionary* headers = [(id)CFHTTPMessageCopyAllHeaderFields(message) autorelease];
        NSString* contentDisposition = [headers objectForKey:@"Content-Disposition"];
        if ([[contentDisposition lowercaseString] hasPrefix:@"form-data;"]) {
          controlName = _ExtractHeaderParameter(contentDisposition, @"name");
          fileName = _ExtractHeaderParameter(contentDisposition, @"filename");
        }
        _controlName = [controlName copy];
        _fileName = [fileName copy];
        _contentType = [[headers objectForKey:@"Content-Type"] retain];
      }
      CFRelease(message);
      if (_controlName) {
        if (_fileName) {
          NSString* path = [NSTemporaryDirectory() stringByAppendingPathComponent:[[NSProcessInfo processInfo] globallyUniqueString]];
          _tmpFile = open([path fileSystemRepresentation], O_CREAT | O_TRUNC | O_WRONLY, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
          if (_tmpFile > 0) {
            _tmpPath = [path copy];
          } else {
            DNOT_REACHED();
            success = NO;
          }
        }
      } else {
        DNOT_REACHED();
        success = NO;
      }
      
      [_parserData replaceBytesInRange:NSMakeRange(0, range.location + range.length) withBytes:NULL length:0];
      _parserState = kParserState_Content;
    }
  }
  
  if ((_parserState == kParserState_Start) || (_parserState == kParserState_Content)) {
    NSRange range = [_parserData rangeOfData:_boundary options:0 range:NSMakeRange(0, _parserData.length)];
    if (range.location != NSNotFound) {
      NSRange subRange = NSMakeRange(range.location + range.length, _parserData.length - range.location - range.length);
      NSRange subRange1 = [_parserData rangeOfData:_newlineData options:NSDataSearchAnchored range:subRange];
      NSRange subRange2 = [_parserData rangeOfData:_dashNewlineData options:NSDataSearchAnchored range:subRange];
      if ((subRange1.location != NSNotFound) || (subRange2.location != NSNotFound)) {
        
        if (_parserState == kParserState_Content) {
          const void* dataBytes = _parserData.bytes;
          NSUInteger dataLength = range.location - 2;
          if (_tmpPath) {
            int result = write(_tmpFile, dataBytes, dataLength);
            if (result == dataLength) {
              if (close(_tmpFile) == 0) {
                _tmpFile = 0;
                GCDWebServerMultiPartFile* file = [[GCDWebServerMultiPartFile alloc] initWithContentType:_contentType fileName:_fileName temporaryPath:_tmpPath];
                [_files setObject:file forKey:_controlName];
                [file release];
              } else {
                DNOT_REACHED();
                success = NO;
              }
            } else {
              DNOT_REACHED();
              success = NO;
            }
            [_tmpPath release];
            _tmpPath = nil;
          } else {
            NSData* data = [[NSData alloc] initWithBytesNoCopy:(void*)dataBytes length:dataLength freeWhenDone:NO];
            GCDWebServerMultiPartArgument* argument = [[GCDWebServerMultiPartArgument alloc] initWithContentType:_contentType data:data];
            [_arguments setObject:argument forKey:_controlName];
            [argument release];
            [data release];
          }
        }
        
        if (subRange1.location != NSNotFound) {
          [_parserData replaceBytesInRange:NSMakeRange(0, subRange1.location + subRange1.length) withBytes:NULL length:0];
          _parserState = kParserState_Headers;
          success = [self _parseData];
        } else {
          _parserState = kParserState_End;
        }
      }
    } else {
      NSUInteger margin = 2 * _boundary.length;
      if (_tmpPath && (_parserData.length > margin)) {
        NSUInteger length = _parserData.length - margin;
        int result = write(_tmpFile, _parserData.bytes, length);
        if (result == length) {
          [_parserData replaceBytesInRange:NSMakeRange(0, length) withBytes:NULL length:0];
        } else {
          DNOT_REACHED();
          success = NO;
        }
      }
    }
  }
  return success;
}

- (NSInteger)write:(const void*)buffer maxLength:(NSUInteger)length {
  DCHECK(_parserData != nil);
  [_parserData appendBytes:buffer length:length];
  return ([self _parseData] ? length : -1);
}

- (BOOL)close {
  DCHECK(_parserData != nil);
  [_parserData release];
  _parserData = nil;
  [_controlName release];
  [_fileName release];
  [_contentType release];
  if (_tmpFile > 0) {
    close(_tmpFile);
    unlink([_tmpPath fileSystemRepresentation]);
  }
  [_tmpPath release];
  return (_parserState == kParserState_End ? YES : NO);
}

- (void)dealloc {
  DCHECK(_parserData == nil);
  [_arguments release];
  [_files release];
  [_boundary release];
  
  [super dealloc];
}

@end