Read line by line.

[Hulag]

I have a little problem. I'm writing a plug-in for a program and I have a problem. I need to parse kind of a script, this script is provided to me as

char *EntScript;

and an example of a script could be

{
"classname" "directional_audio"
"angle" "270"
}
{
"classname" "audio_source"
"origin" "0 0 24"
}

Now I don't need the code to parse or anything, I want to write that code myself, the problem is that I don't know how to parse that string line by line. I know that if EntScript was a FILE kind of variable then I would use fgets because it stops as soon as it finds a line break or EOF, whichever comes first. How can I do a similar function that instead of taking a FILE variable uses the variable already defined?
Thanks.

[Codeplug]

How do I work with file in C

gg

[Hulag]

Originally posted by Codeplug
How do I work with file in C

gg

That doesn't really help me. I know how to open and write files, but I don't have to. All the info I need is in EntScript, there is no need to read any file, and even if I had to open a file I wouldn't know how since there are no specifications for this format. Also, I don't think putting the contents of EntScript back in a file so I can use fgets would be good, it would be a working solution but just as kind of a hack(one slow hack). Thanks anyway.

[Codeplug]

Can you clarify your question a little more?

What is this supposed to be?

{
"classname" "directional_audio"
"angle" "270"
}
{
"classname" "audio_source"
"origin" "0 0 24"
}

gg

[twm]

>How can I do a similar function that instead of taking a FILE variable uses the variable already defined?
Sounds like you want sscanf if the defined variable you're talking about is EntScript...

[Hulag]

Originally posted by Codeplug
Can you clarify your question a little more?

What is this supposed to be?

{
"classname" "directional_audio"
"angle" "270"
}
{
"classname" "audio_source"
"origin" "0 0 24"
}

gg

That's a its just a short example of a script I have to deal with, that's what I have to parse.

Originally posted by twm
>How can I do a similar function that instead of taking a FILE variable uses the variable already defined?
Sounds like you want sscanf if the defined variable you're talking about is EntScript...

sscanf isn't flexible enough, it would work perfectly on the sample script I showed, but the script could be(and usually is) more complex. I need to be able to read character by character or line by line the contents of EntScript.

[Dave_Sinkula]

Originally posted by Hulag
sscanf isn't flexible enough, it would work perfectly on the sample script I showed, but the script could be(and usually is) more complex. I need to be able to read character by character or line by line the contents of EntScript.

Something like this isn't workable?

#include <stdio.h>

int main(void)
{
   const char EntScript[] =
   "{\n"
   "\"classname\" \"directional_audio\"\n"
   "\"angle\" \"270\"\n"
   "}\n"
   "{\n"
   "\"classname\" \"audio_source\"\n"
   "\"origin\" \"0 0 24\"\n"
   "}";
   const char *ptr = EntScript;
   char text[80];
   int i, line = 0;
   while ( sscanf(ptr, "%79[^\n]%n%*c", text, &i) == 1 )
   {
      ptr += i + 1;
      printf("line %d: %s\n", ++line, text);
   }
   return 0;
}

/* my output
line 1: {
line 2: "classname" "directional_audio"
line 3: "angle" "270"
line 4: }
line 5: {
line 6: "classname" "audio_source"
line 7: "origin" "0 0 24"
line 8: }
*/

[Codeplug]

#include <stdio.h>
#include <string.h>

int main()
{
    int n, len;

    /* notice the newlines (\n) and escapes for quotes (\") */
    char script[] = 
    {
        "{\n"
        "\"classname\" \"directional_audio\"\n"
        "\"angle\" \"270\"\n"
        "}\n"
        "{\n"
        "\"classname\" \"audio_source\"\n"
        "\"origin\" \"0 0 24\"\n"
        "}\n"
    };

    printf("Here is the script\n");
    printf("*********************************\n");
    printf(script);
    printf("*********************************\n\n");

    printf("Now here it is one character at a time\n");
    printf("*********************************\n");
    len = strlen(script);
    for (n = 0; n < len; n++)
    {
        printf ("%c", script[n]);
    }
    printf("*********************************\n\n");

    return 0;
}

gg

[EDIT]
Nice. Two examples to look at

[Salem]

> need to be able to read character by character or line by line the contents of EntScript.
So write your own version of fgets(), which reads from a buffer instead of a FILE

Heh, make it 3 examples....

#include <stdio.h>
#include <string.h>

char *EntScript =
"\{\n"
"\"classname\" \"directional_audio\"\n"
"\"angle\" \"270\"\n"
"}\n"
"{\n"
"\"classname\" \"audio_source\"\n"
"\"origin\" \"0 0 24\"\n"
"}\n";

char *mySgets ( char *buff, size_t size, char **input ) {
    char    *p = *input;
    if ( *p == '\0' || size == 0 ) {
        return NULL;
    } else {
        char    *q = buff;
        while ( --size > 0 ) {
            char    ch = *p;
            if ( ch == '\0' ) break;    /* end of string */
            *q++ = *p++;                /* copy a char to our line buffer */
            if ( ch == '\n' ) break;    /* end of line */
        }
        *q = '\0';      /* terminate the string in buff */
        *input = p;     /* where we got to */
        return buff;    /* what fgets normally returns on success */
    }
}

int main ( ) {
    char buff[BUFSIZ];
    char *p = EntScript;

    printf( ">>%s<<\n", EntScript );

    /* get a line from a string, in the style of fgets() */
    while ( mySgets( buff, BUFSIZ, &p ) != NULL ) {
        printf( "Line = %s", buff );
    }
    return 0;
}

[Hulag]

Thanks for the solutions provided, I will see which one works the best and be back with a response. Thanks again.