upload.php

gistfile1.php

<?php
/*
 * 图片上传处理 
 * todo: 防止post大量图片攻击
 */

ini_set('gd.jpeg_ignore_warning', 1);

$config=array();

$config['img']   = array("jpg","bmp","gif","png","jpeg"); //文件类型
$config['size']  = 10240; //大小
$config['width'] = 400; //定义宽度，高度按等比缩放。
$config['dir']   = getcwd() . "/tmp/"; //目录

if(isset($_FILES['avatar']['tmp_name']) && is_uploaded_file($_FILES['avatar']['tmp_name'])){

	$filearr=pathinfo($_FILES['avatar']['name']);

	$filetype=$filearr["extension"];

	if(!in_array($filetype, $config["img"])){
		die("FAILE:错误的文件类型！");
	}

	if($_FILES['avatar']['size']> $config['size']*1024){
		die("FAILE:上传的文件不能超过".$config["size"]."KB！");
	}

	$newfile = gen_name();
	
	$res = resize($_FILES['avatar']['tmp_name'], $config["dir"].$newfile);

	if($res){
		list($width, $heigh, $image_type) = getimagesize($config["dir"].$newfile);
		
		$msg=array(
			'status' => 1,
			'width'=>$width,
			'height'=>$heigh,
			'file'=>$newfile,
		);
		if(isset($_GET['mode']) && $_GET['mode'] == 'debug'){
		      echo '<img src="/tmp/'.$newfile.'" />';
		}else{
            echo json_encode($msg);
            die;
        }
	}else{
		die('FAILE:上传失败');
	}
}elseif(isset($_GET['mode']) && $_GET['mode'] == 'debug'){
	// 测试
	echo'
        <form action="" method="post" enctype="multipart/form-data">
        <input name="avatar" size="40" type="file" />
        <input name="su" size="40" type="submit" />
    ';
}else{
    die(json_encode(array('code'=>400)));
}

//生成唯一图片名
function gen_name()
{
	$server_name = $_SERVER['SERVER_NAME'];
	$pid = (function_exists('posix_getpid')) ? posix_getpid() : rand(16384, 32767);
	$seed = rand(0, 32767);
	$t_stamp = str_replace(' ', '', microtime());
	$tmp_1 = md5($seed . '-' . $t_stamp);
	$tmp_2 = md5($pid . '-' . $server_name);
	$tmp_3 = md5($tmp_1 . $tmp_2);
	$key = substr($tmp_3, 4, 16);
	$user_id = $key . '_' . substr($t_stamp, -7);
	return $user_id.'.jpg';
}

/*
    裁切图片函数
    $image 原图
    $dst  裁切后的小图
    $dw, $dh 新的宽度和高度
    $type 1=等比缩小，裁掉部分区域 2=等比缩小 3=等比缩小，保留全部，补空白
*/
function resize($image,$dst, $dw=400,$dh=400,$type=3){   
   if(!file_exists($image)){   
        return false;   
   }

   #取得文件的类型,根据不同的类型建立不同的对象   
   $imginfo=getimagesize($image);   
   switch($imginfo[2]){   
       case 1:   
        $img = @imagecreatefromgif($image);   
       break;   
       case 2:   
        $img = @imagecreatefromjpeg($image);   
       break;   
       case 3:   
        $img = @imagecreatefrompng($image);   
       break;   
   }   
  
   if(empty($img)){   
        if($type!=1){unlink($image);}   
        return false;   
   }   

   #如果是执行调整尺寸操作则   
   if($type==1){   
        $w=imagesx($img);   
        $h=imagesy($img);   
        $width = $w;   
        $height = $h;   
  
        $nimg = imagecreatetruecolor($dw,$dh);   
        if($h/$w>$dh/$dw){ #高比较大   
             $width=$dw;   
             $height=$h*$dw/$w;   
             $intnh=$height-$dh;   
             imagecopyresampled($nimg, $img, 0, -$intnh/1.8, 0, 0, $dw, $height, $w, $h);   
        }else{     #宽比较大   
             $height=$dh;   
             $width=$w*$dh/$h;   
             $intnw=$width-$dw;   
             imagecopyresampled($nimg, $img, -$intnw/1.8, 0, 0, 0, $width, $dh, $w, $h);   
        }   
        imagejpeg ($nimg,$image);   
        return true;   
   }elseif(($type==2 || $type==3)){   
        $w=imagesx($img);   
        $h=imagesy($img);   
        $width = $w;   
        $height = $h;   
        if($width>$dw){   
             $par=$dw/$width;   
             $width=$dw;   
             $height=$height*$par;   
             if($height>$dh){   
                  $par=$dh/$height;   
                  $height=$dh;   
                  $width=$width*$par;   
            }   
        }elseif($height>$dh){   
             $par=$dh/$height;   
             $height=$dh;   
             $width=$width*$par;   
             if($width>$dw){   
                  $par=$dw/$width;   
                  $width=$dw;   
                  $height=$height*$par;   
             }   
        }else{   
             $width=$width;   
             $height=$height;   
        }   
        if($type==3){   
            $nimg = imagecreatetruecolor($dw,$dh);     #新建一个真彩色画布   
            imagealphablending($nimg, false);   
            imagesavealpha($nimg, true);   
            $white = imagecolorallocatealpha($nimg,255,255,255,127);   
            imagefill($nimg,0,0,$white);   
            $tmpw=($dw-$width)/2;
            $tmph=($dh-$height)/2;
            imagecopyresampled($nimg,$img,$tmpw,$tmph,0,0,$width,$height,$w,$h);#重采样拷贝部分图像并调整大小   
        }
        elseif($type==1){   
            $nimg = imagecreatetruecolor($width,$height);     #新建一个真彩色画布   
            imagecopyresampled($nimg,$img,0,0,0,0,$width,$height,$w,$h);#重采样拷贝部分图像并调整大小   
        }   
        imagejpeg ($nimg,$dst);                  #以jpeg格式将图像输出到浏览器或文件   
        return $image;   
   }   
}