www.digitalmars.com         C & C++   DMDScript  

digitalmars.D.learn - D1: std.md5: corrections for the given example

reply notna <notna.remove.this ist-einmalig.de> writes:
Hi.

In the given example of the D1 std.md5, this line can be found:
while ((len = fread(buffer, 1, buffer.sizeof, file)) != 0)

This isn't working here (DMD v1.042, Windows XP Pro). I had to replace 
it with:
while ((len = fread(buffer.ptr, cast(uint)1, buffer.sizeof, file)) != 0)
                            ^^^  ^^^^^^^^^^

Someone may want to check & adopt this in the std.md5 module...

Thanks & regards
notna
Sep 16 2009
parent reply Stewart Gordon <smjg_1998 yahoo.com> writes:
notna wrote:
<snip>

 This isn't working here (DMD v1.042, Windows XP Pro). I had to replace 
 it with:
 while ((len = fread(buffer.ptr, cast(uint)1, buffer.sizeof, file)) != 0)
                            ^^^  ^^^^^^^^^^




The .ptr is necessary, but the cast(uint) isn't.  Even if a change of 
type were necessary, just 1U would do.  (U is a suffix meaning unsigned. 
  There's also L meaning long.)

Stewart.
Sep 16 2009
parent reply notna <notna.remove.this ist-einmalig.de> writes:
Stewart Gordon schrieb:

 The .ptr is necessary, but the cast(uint) isn't.  Even if a change of 
 type were necessary, just 1U would do.  (U is a suffix meaning unsigned. 
  There's also L meaning long.)
 
 Stewart.



Thank Stewart.

As the std.md5-example is not working with "unicode" file names 
(fopen...) I rewrote the "MDFile" function and use "file.readBlock" 
instead now. Maybe the std.md5 example should be changed to use a 
"file.read" or "file.readBlock".

Here is my code (I've checkedthe file exists and is readable before):

string MD5File(string fileName) {
	
	File file = new File;
	MD5_CTX context;
	int len;
	ubyte[4 * 1024] buffer;
	ubyte digest[16];

	file.open(fileName, FileMode.In);	
	context.start();
	while ((len = file.readBlock(buffer.ptr, buffer.sizeof)) != 0)
		context.update(buffer[0 .. len]);
	context.finish(digest);
	file.close();
	
	string MD5Sum = (digestToString(digest));
	return MD5Sum;
	
}

Regards
notna
Sep 16 2009
parent reply downs <default_357-line yahoo.de> writes:
notna wrote:

 Stewart Gordon schrieb:

 The .ptr is necessary, but the cast(uint) isn't.  Even if a change of
 type were necessary, just 1U would do.  (U is a suffix meaning
 unsigned.  There's also L meaning long.)

 Stewart.



 Thank Stewart.
 
 As the std.md5-example is not working with "unicode" file names
 (fopen...) I rewrote the "MDFile" function and use "file.readBlock"
 instead now. Maybe the std.md5 example should be changed to use a
 "file.read" or "file.readBlock".
 
 Here is my code (I've checkedthe file exists and is readable before):
 
 string MD5File(string fileName) {
     
     File file = new File;




     MD5_CTX context;
     int len;




     ubyte[4 * 1024] buffer;
     ubyte digest[16];
 
     file.open(fileName, FileMode.In);   




     context.start();
     while ((len = file.readBlock(buffer.ptr, buffer.sizeof)) != 0)



while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))


         context.update(buffer[0 .. len]);
     context.finish(digest);
     file.close();
     




     string MD5Sum = (digestToString(digest));
     return MD5Sum;




     
 }
 
 Regards
 notna
Sep 17 2009
next sibling parent notna <notna.remove.this ist-einmalig.de> writes:
downs wrote:

 scope file = new File(fileName, FileMode.In);
 // int len;
 while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))
 // return digestToString(digest);



Thanks, that looks "cleaner"...
Sep 17 2009
prev sibling parent reply Stewart Gordon <smjg_1998 yahoo.com> writes:
downs wrote:
<snip>

 while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))




md5_example_2.d(7): expression expected, not 'auto'
md5_example_2.d(7): found 'len' when expecting ')'
md5_example_2.d(7): found '=' instead of statement

(this is line 7 after I removed comments and blank lines from your edit)

Stewart.
Sep 17 2009
next sibling parent notna <notna.remove.this ist-einmalig.de> writes:
Stewart Gordon schrieb:

 downs wrote:
 <snip>

 while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))



 
 md5_example_2.d(7): expression expected, not 'auto'
 md5_example_2.d(7): found 'len' when expecting ')'
 md5_example_2.d(7): found '=' instead of statement
 
 (this is line 7 after I removed comments and blank lines from your edit)
 
 Stewart.



yeah, you're right again.
sorr, I had'n the time to test as I posted the message before. that's 
why I wrote "it looks cleaner" :-(

anyhow, also the " != 0 " is needed. otherwise I get this:
Error: '=' does not give a boolean result

so, the working code is:

string MD5File(string fileName) {
	
	File file = new File(fileName, FileMode.In);
	MD5_CTX context;
	int len;
	ubyte[4 * 1024] buffer;
	ubyte digest[16];
	
	context.start();
	while ((len = file.readBlock(buffer.ptr, buffer.sizeof)) != 0)
		context.update(buffer[0 .. len]);
	context.finish(digest);
	
	file.close();
	
	return digestToString(digest);
	
}
Sep 17 2009
prev sibling parent reply downs <default_357-line yahoo.de> writes:
Stewart Gordon wrote:

 downs wrote:
 <snip>

 while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))



 
 md5_example_2.d(7): expression expected, not 'auto'
 md5_example_2.d(7): found 'len' when expecting ')'
 md5_example_2.d(7): found '=' instead of statement
 
 (this is line 7 after I removed comments and blank lines from your edit)
 
 Stewart.



God I'm stupid.

Sorry.

I guess I wish that worked.
Sep 17 2009
parent reply grauzone <none example.net> writes:
downs wrote:

 Stewart Gordon wrote:

 downs wrote:
 <snip>

 while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))




 md5_example_2.d(7): expression expected, not 'auto'
 md5_example_2.d(7): found 'len' when expecting ')'
 md5_example_2.d(7): found '=' instead of statement

 (this is line 7 after I removed comments and blank lines from your edit)

 Stewart.



 God I'm stupid.
 
 Sorry.
 
 I guess I wish that worked.



http://d.puremagic.com/issues/enter_bug.cgi
Sep 18 2009
parent reply notna <notna.remove.this ist-einmalig.de> writes:
grauzone schrieb:


 md5_example_2.d(7): expression expected, not 'auto'
 md5_example_2.d(7): found 'len' when expecting ')'
 md5_example_2.d(7): found '=' instead of statement

 (this is line 7 after I removed comments and blank lines from your edit)

 Stewart.



 God I'm stupid.

 Sorry.

 I guess I wish that worked.



 http://d.puremagic.com/issues/enter_bug.cgi



???

What do you wanna tell us? That
   while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))
has to work and does not because it's a bug? And that's why you think a 
bug report should be opened?
Sep 18 2009
next sibling parent Stewart Gordon <smjg_1998 yahoo.com> writes:
notna wrote:

 grauzone schrieb:




 http://d.puremagic.com/issues/enter_bug.cgi



 ???
 
 What do you wanna tell us?



Where to report bugs.


 That
   while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))
 has to work and does not because it's a bug?



If you want to know whether a piece of code is legal or not, try reading 
the D documentation.


 And that's why you think a bug report should be opened?



No, that this code example in the Phobos documentation is wrong and 
therefore a bug report should be opened.

Stewart.
Sep 18 2009
prev sibling parent reply grauzone <none example.net> writes:
notna wrote:

 grauzone schrieb:
 

 md5_example_2.d(7): expression expected, not 'auto'
 md5_example_2.d(7): found 'len' when expecting ')'
 md5_example_2.d(7): found '=' instead of statement

 (this is line 7 after I removed comments and blank lines from your 
 edit)

 Stewart.



 God I'm stupid.

 Sorry.

 I guess I wish that worked.



 http://d.puremagic.com/issues/enter_bug.cgi



 ???
 
 What do you wanna tell us? That
   while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))
 has to work and does not because it's a bug? And that's why you think a 
 bug report should be opened?



Enhancement request to allow auto in while, to make it consistent with 
if. (You can write "if(auto x = foo()) {...}")
Sep 19 2009
parent Stewart Gordon <smjg_1998 yahoo.com> writes:
grauzone wrote:

 notna wrote:




 What do you wanna tell us? That
   while (auto len = file.readBlock(buffer.ptr, buffer.sizeof))
 has to work and does not because it's a bug? And that's why you think 
 a bug report should be opened?



 Enhancement request to allow auto in while, to make it consistent with 
 if. (You can write "if(auto x = foo()) {...}")



The chance of an enhancement request being landed in the D1 line has 
always been small, and now it's even smaller.

Stewart.
Sep 19 2009