update

README.md

@@ -5,3 +5,5 @@
 #### 1 create dedicated length random vector
 #### 2 calculate the crc32
 #### 3 save to file
+
+### create_crc_data.py

create_crc_data.py

@@ -6,45 +6,76 @@
 import sys
 import random
 
-
-
 def getCrc32(filename):
 	with open(filename, 'rb') as f:
 		return crc32(f.read())&0xffffffff
 
-def putCrc32(file_path, msg):
-    f=open(file_path,"w")
-    f.write(msg)
+def putCrc32(file_name, data):
+    f=open(file_name,"w")
+    f.write(data)
     f.close
 
 # 通过random.randint(a, b)方法得到随机数字
 def generate_random_str(length):
-	random_str=""
-	base_str="ABCDEFGHIGKLMNOPQRSTUVWXYZabcdefghigklmnopqrstuvwxyz0123456789!@#$%^&*()"
-	n=len(base_str)-1
-	for i in range(int(length)):
-	    random_str+=base_str[random.randint(0,n)]  
-	return random_str
+
+    random_str=""
+    # base_str="ABCDEFGHIGKLMNOPQRSTUVWXYZabcdefghigklmnopqrstuvwxyz0123456789!@#$%^&*"
+    base_str="ABCDEFGHIGKLMNOPQRSTUVWXYZabcdefghigklmnopqrstuvwxyz0123456789"
+    print(type(base_str))
+    print ("base_str %s" % len(base_str))
+    n=len(base_str)-1
+    # n=61
+
+    for i in range(int(length)):
+        random_str+=base_str[random.randint(0,n)]  
+
+    return random_str
 
 if __name__ == '__main__':
 
     if len(sys.argv) < 2:
         print ("Usage: python create_crc_data.py <data_length>")
         exit(-1)
 
+    if (False == os.path.isdir('data')):
+        os.mkdir('data')
+
     data_length = sys.argv[1]
-    file_name = str(data_length) +'.dat'
 
-    putCrc32(file_name, generate_random_str(data_length))
+    #todo 参数检查
+
+    if (data_length.endswith('b') | data_length.endswith('B')):
+        data_len = data_length[0:-1]
+        lenth = int(data_len)
+    elif (data_length.endswith('k') | data_length.endswith('K')):
+        data_len = data_length[0:-1]
+        print (data_len)
+        lenth = int(data_len)*1024
+    elif (data_length.endswith('m') | data_length.endswith('M')):
+        data_len = data_length[0:-1]
+        lenth = int(data_len)*1024*1024
+    else:
+        lenth = int(data_length)
+
+    print ("data length is %s----%s byte" % (data_length, lenth))
+
+    # name the input file
+    file_name = "data/"+ str(data_length) +'.dat'
+    print("input_file_name  %s" % file_name)
 
+    #reserve the random data file
+    putCrc32(file_name, generate_random_str(lenth))
 
+    # CRC32 calculation
     checksum=getCrc32(file_name)
 
+    #name the output file
     output_file = file_name.replace('.dat','_crc32.dat')
 
+    #reserve the crc32 result
     putCrc32(output_file, hex(checksum))
 
-    print ("Reserve the crc data in %s" % output_file)
+    print ("Reserve crc data in %s" % output_file)
 
     print ("Crc:",(hex(checksum)))