• Puming Zhao (11/11) Jan 05 2012 Hi, I'm new in D programming, and does not have much C experience either...
• Joshua Reusch (7/20) Jan 05 2012 timeval tv);
• Timon Gehr (2/32) Jan 05 2012 D string literals are zero-terminated.
• Joshua Reusch (3/40) Jan 05 2012 Sure ? dlang.org says they are not:
• Joshua Reusch (3/5) Jan 05 2012 Sorry, in the printf section: "String literals already have a 0 appended...
• Andrej Mitrovic (11/11) Jan 05 2012 Your problem is that you're calling printf on a static char array. If
• bearophile (6/8) Jan 05 2012 I think C just requires:
• Puming (21/36) Jan 05 2012 Thanks for the tip. I've changed code as you suggested.
• Mike Parker (9/43) Jan 05 2012 I think the problem still lies with your declaration of the integer
• Puming (7/16) Jan 05 2012 I changed c_long to long and it actually works !!! Thanks very
• Puming (6/6) Jan 05 2012 Here is what I've got so far:
• bearophile (4/5) Jan 06 2012 In C "long long" isn't always 64 bit.
• Mike Parker (3/6) Jan 06 2012 Well, either the documentation is wrong or the implementation is. Looks
• Johannes Pfau (7/15) Jan 06 2012 The documentation is wrong. c_long is meant to be used _only_ for C's "l...
• Andrej Mitrovic (4/5) Jan 06 2012 That was my fault. I was going to fix the original docs which had no
• Johannes Pfau (26/43) Jan 05 2012 in hiredis.d
• Puming (5/8) Jan 05 2012 Thanks. I've changed `int integer` to `c_long integer` according

Puming Zhao <zhaopuming gmail.com> writes:

Hi, I'm new in D programming, and does not have much C experience either.  After
reading TDPL book and playing with some sample codes, I came to decide to try
something more `practical`. I began with a Redis client binding from Hiredis C
code.
Hiredis is a small lib, and seems very simple to bind to D.

My code on github:

https://github.com/zhaopuming/dredis

But I went into problems that I don't know how to solve. When running example.d
I
went into segment fault, and can't get redisReply from a redis command. I tried
to
google it but got nothing.

So my question is, could some one with more knowledge in redis or C/D look into
my
code and see what's wrong ? Or is there already a Redis binding exists?

Joshua Reusch <yoschi arkandos.de> writes:

Am 05.01.2012 17:21, schrieb Puming Zhao:
 Hi, I'm new in D programming, and does not have much C experience either. 
After
 reading TDPL book and playing with some sample codes, I came to decide to try
 something more `practical`. I began with a Redis client binding from Hiredis C
code.
 Hiredis is a small lib, and seems very simple to bind to D.

 My code on github:

 https://github.com/zhaopuming/dredis

 But I went into problems that I don't know how to solve. When running
example.d I
 went into segment fault, and can't get redisReply from a redis command. I
tried to
 google it but got nothing.

 So my question is, could some one with more knowledge in redis or C/D look
into my
 code and see what's wrong ? Or is there already a Redis binding exists?

dredis.d:
 redisContext* redisConnectWithTimeout(const char* ip, int port, 

timeval tv);

example.d:
 redisConnectWithTimeout("127.0.0.1", 6379, timeout);


D strings do not end with an \0 byte !
You can use std.string.toStringz to convert them to C's const char*

  -- Joshua

Timon Gehr <timon.gehr gmx.ch> writes:

On 01/05/2012 07:14 PM, Joshua Reusch wrote:
 Am 05.01.2012 17:21, schrieb Puming Zhao:
 Hi, I'm new in D programming, and does not have much C experience
 either. After
 reading TDPL book and playing with some sample codes, I came to decide
 to try
 something more `practical`. I began with a Redis client binding from
 Hiredis C code.
 Hiredis is a small lib, and seems very simple to bind to D.

 My code on github:

 https://github.com/zhaopuming/dredis

 But I went into problems that I don't know how to solve. When running
 example.d I
 went into segment fault, and can't get redisReply from a redis
 command. I tried to
 google it but got nothing.

 So my question is, could some one with more knowledge in redis or C/D
 look into my
 code and see what's wrong ? Or is there already a Redis binding exists?

 dredis.d:
  > redisContext* redisConnectWithTimeout(const char* ip, int port,
 timeval tv);

 example.d:
  > redisConnectWithTimeout("127.0.0.1", 6379, timeout);


 D strings do not end with an \0 byte !
 You can use std.string.toStringz to convert them to C's const char*

 -- Joshua

D string literals are zero-terminated.

Joshua Reusch <yoschi arkandos.de> writes:

Am 05.01.2012 19:44, schrieb Timon Gehr:
 On 01/05/2012 07:14 PM, Joshua Reusch wrote:
 Am 05.01.2012 17:21, schrieb Puming Zhao:
 Hi, I'm new in D programming, and does not have much C experience
 either. After
 reading TDPL book and playing with some sample codes, I came to decide
 to try
 something more `practical`. I began with a Redis client binding from
 Hiredis C code.
 Hiredis is a small lib, and seems very simple to bind to D.

 My code on github:

 https://github.com/zhaopuming/dredis

 But I went into problems that I don't know how to solve. When running
 example.d I
 went into segment fault, and can't get redisReply from a redis
 command. I tried to
 google it but got nothing.

 So my question is, could some one with more knowledge in redis or C/D
 look into my
 code and see what's wrong ? Or is there already a Redis binding exists?

 dredis.d:
 redisContext* redisConnectWithTimeout(const char* ip, int port,

 timeval tv);

 example.d:
 redisConnectWithTimeout("127.0.0.1", 6379, timeout);


 D strings do not end with an \0 byte !
 You can use std.string.toStringz to convert them to C's const char*

 -- Joshua

 D string literals are zero-terminated.

Sure ? dlang.org says they are not: 
http://www.d-programming-language.org/arrays.html#strings

Joshua Reusch <yoschi arkandos.de> writes:

 Sure ? dlang.org says they are not:
 http://www.d-programming-language.org/arrays.html#strings

Sorry, in the printf section: "String literals already have a 0 appended 
to them, so can be used directly"

I missed this.

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

Your problem is that you're calling printf on a static char array. If
you're going to use printf you have to use it on the .ptr (pointer)
field of the static array. Replace this call:

    printf("Connection error: %s\n", c.errstr);
with
    printf("Connection error: %s\n", c.errstr.ptr);

On my end I get:
Connection error: Connection refused

Also I think you should replace the "int integer" in struct redisReply
to "long integer". I think `long long` in C is 8 bytes, which is the
equivalent to D's long type.

bearophile <bearophileHUGS lycos.com> writes:

Andrej Mitrovic:

 I think `long long` in C is 8 bytes, which is the
 equivalent to D's long type.

I think C just requires:
sizeof(long long int) >= sizeof(long int).

For the actual size I think you have to ask to the C compiler.

Bye,
bearophile

"Puming" <zhaopuming gmail.com> writes:

On Thursday, 5 January 2012 at 22:02:25 UTC, Andrej Mitrovic 
wrote:

 Your problem is that you're calling printf on a static char 
 array. If
 you're going to use printf you have to use it on the .ptr 
 (pointer)
 field of the static array. Replace this call:

   printf("Connection error: %s\n", c.errstr);
 with
   printf("Connection error: %s\n", c.errstr.ptr);

 On my end I get:
 Connection error: Connection refused

 Also I think you should replace the "int integer" in struct 
 redisReply
 to "long integer". I think `long long` in C is 8 bytes, which 
 is the
 equivalent to D's long type.

Thanks for the tip. I've changed code as you suggested.
And for the type `long long`, I changed `int` to `c_long` (in 
core.stdc.config) according to http://dlang.org/interfaceToC.html

But there is still problem. My code does actually connect, as I 
have a redis-server running on my machine, and the commands 
actually runned, as I use a redis-cli and found that "foo : bar" 
is actually set into redis. But

---
  reply = cast(redisReply*) redisCommand(c, "GET foo");
  writefln("GET foo: %s", *reply);
  writefln(to!string(reply.str));
----

output these:

---
GET foo: redisReply(1, 0, 0, 2, 152397072, 0)
80B1F42
段错误  // (which is Chinese for Segfault)
---

So maybe I got it wrong when converting char* to string?

Mike Parker <aldacron gmail.com> writes:

On 1/6/2012 11:38 AM, Puming wrote:
 On Thursday, 5 January 2012 at 22:02:25 UTC, Andrej Mitrovic wrote:

 Your problem is that you're calling printf on a static char array. If
 you're going to use printf you have to use it on the .ptr (pointer)
 field of the static array. Replace this call:

 printf("Connection error: %s\n", c.errstr);
 with
 printf("Connection error: %s\n", c.errstr.ptr);

 On my end I get:
 Connection error: Connection refused

 Also I think you should replace the "int integer" in struct redisReply
 to "long integer". I think `long long` in C is 8 bytes, which is the
 equivalent to D's long type.

 Thanks for the tip. I've changed code as you suggested.
 And for the type `long long`, I changed `int` to `c_long` (in
 core.stdc.config) according to http://dlang.org/interfaceToC.html

 But there is still problem. My code does actually connect, as I have a
 redis-server running on my machine, and the commands actually runned, as
 I use a redis-cli and found that "foo : bar" is actually set into redis.
 But

 ---
 reply = cast(redisReply*) redisCommand(c, "GET foo");
 writefln("GET foo: %s", *reply);
 writefln(to!string(reply.str));
 ----

 output these:

 ---
 GET foo: redisReply(1, 0, 0, 2, 152397072, 0)
 80B1F42
 段错误 // (which is Chinese for Segfault)
 ---

 So maybe I got it wrong when converting char* to string?

I think the problem still lies with your declaration of the integer 
field. c_long in D is supposed to be equivalent to the long type in C, 
*not* long long. It is declared as 32 bits on a 32-bit system and 64 
bits on a 64-bit system. I believe that in practice, most C compilers 
implement long long as 64 bits on both 32- and 64-bit systems. I 
recommend you use long on the D side, rather than c_long. And, actually, 
it would be best to compile a test with the same C compiler used to 
compile redis to verify the size of long long.

"Puming" <zhaopuming gmail.com> writes:

 I think the problem still lies with your declaration of the 
 integer field. c_long in D is supposed to be equivalent to the 
 long type in C, *not* long long. It is declared as 32 bits on a 
 32-bit system and 64 bits on a 64-bit system. I believe that in 
 practice, most C compilers implement long long as 64 bits on 
 both 32- and 64-bit systems. I recommend you use long on the D 
 side, rather than c_long. And, actually, it would be best to 
 compile a test with the same C compiler used to compile redis 
 to verify the size of long long.

I changed c_long to long and it actually works !!! Thanks very 
much. Now I'm wondering should I use `long` or do some static 
check for the type just like what c_long does for C' long type? 
I'm only using 32bit Ubuntu, so not able to check this on other 
systems. Wonder whether there is a c_long_long type.

In http://dlang.org/interfaceToC.html it says in 32bit system 
c_long is equivalent to `long long` in C. Is this wrong?

"Puming" <zhaopuming gmail.com> writes:

Here is what I've got so far:

1. "long long" in C is always 64bit, so in D it's "long";
2. C's char* string should be converted to!string when used in 
"writeln";
3. String literals in D -IS- zero terminated;

And now it's working fine. Thanks everybody :)

bearophile <bearophileHUGS lycos.com> writes:

Puming:

 1. "long long" in C is always 64bit, so in D it's "long";

In C "long long" isn't always 64 bit.

Bye,
bearophile

Mike Parker <aldacron gmail.com> writes:

On 1/6/2012 2:34 PM, Puming wrote:

 In http://dlang.org/interfaceToC.html it says in 32bit system c_long is
 equivalent to `long long` in C. Is this wrong?

Well, either the documentation is wrong or the implementation is. Looks 
like one for Bugzilla.

Johannes Pfau <spam example.com> writes:

Mike Parker wrote:

 On 1/6/2012 2:34 PM, Puming wrote:

 In http://dlang.org/interfaceToC.html it says in 32bit system c_long is
 equivalent to `long long` in C. Is this wrong?

 
 Well, either the documentation is wrong or the implementation is. Looks
 like one for Bugzilla.

The documentation is wrong. c_long is meant to be used _only_ for C's "long" 
type, so it must be 32bit for 32bit architectures and 64bit for (most) 64bit 

bit_data_models

No need to file a bug though, I posted a fix here: https://github.com/D-
Programming-Language/d-programming-language.org/pull/55

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

On 1/6/12, Johannes Pfau <spam example.com> wrote:
 The documentation is wrong.

That was my fault. I was going to fix the original docs which had no
mention of c_long/c_ulong and I ended up screwing up the tables.
Sorry!

Johannes Pfau <spam example.com> writes:

Puming Zhao wrote:

 Hi, I'm new in D programming, and does not have much C experience either. 
 After reading TDPL book and playing with some sample codes, I came to
 decide to try something more `practical`. I began with a Redis client
 binding from Hiredis C code. Hiredis is a small lib, and seems very simple
 to bind to D.
 
 My code on github:
 
 https://github.com/zhaopuming/dredis
 
 But I went into problems that I don't know how to solve. When running
 example.d I went into segment fault, and can't get redisReply from a redis
 command. I tried to google it but got nothing.
 
 So my question is, could some one with more knowledge in redis or C/D look
 into my code and see what's wrong ? Or is there already a Redis binding
 exists?

in hiredis.d
------------------------
struct redisReply {
    int type; /* REDIS_REPLY_* */
    int integer; /* The integer when type is REDIS_REPLY_INTEGER */
    int len; /* Length of string */
    char* str; /* Used for both REDIS_REPLY_ERROR and REDIS_REPLY_STRING */
    size_t elements; /* number of elements, for REDIS_REPLY_ARRAY */
    redisReply** element; /* elements vector for REDIS_REPLY_ARRAY */
};
------------------------

but in hiredis.h
------------------------
typedef struct redisReply {
    int type; /* REDIS_REPLY_* */
    long long integer; /* The integer when type is REDIS_REPLY_INTEGER */
    int len; /* Length of string */
    char *str; /* Used for both REDIS_REPLY_ERROR and REDIS_REPLY_STRING */
    size_t elements; /* number of elements, for REDIS_REPLY_ARRAY */
    struct redisReply **element; /* elements vector for REDIS_REPLY_ARRAY */
} redisReply;
------------------------

So you have "int integer;" in D and "long long integer;" in C, which doesn't 
match. I'm not sure what size "long long" is in C, but I guess you need 
"long" in D?

"Puming" <zhaopuming gmail.com> writes:

 So you have "int integer;" in D and "long long integer;" in C, 
 which doesn't match. I'm not sure what size "long long" is in 
 C, but I guess you need "long" in D?

Thanks. I've changed `int integer` to `c_long integer` according 
to this page

http://dlang.org/interfaceToC.html

c_long is in core.stdc.config

But I still can not get reply.str right...