General How to go about this question?

I'm working on this code that I'm hoping can take a C file and rearrange bad indentation, ignore comments, remove whitespace etc to get it to an agreed format.

Heres what I have so far:

Code:

---

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

char *check=0;
char ch=!EOF;
char* compare="int main";
int i, c, a, indent;
FILE *input;
FILE *output;

void Print()
{
fprintf(output, "%c", ch);
}


void Check()
{
check = realloc( check, i+1 );
check[i] = fgetc(input);
ch = check[i];
if(ch == '\t')
{
Check();
}
}

void EndofLine()
{
for(i = i; ch != '\n'; i++)
{
check = realloc( check, i+1 );
check[i] = fgetc(input);
ch = check[i];
fprintf(output, "%c", ch);
}
}

void EndofComment()
{
i++;
check = realloc( check, i+1 );
check[i] = fgetc(input);
ch = check[i];

if(ch == '*')
{
Print();
EndofLine();
}else{
i--;
}
}

void MainCheck()
{
i++;
check[i] = '\0';
int strcmp(
  const char *check,
  const char *compare
);
i--;
}

int main(int argc, char *argv[])
{
input = fopen(argv[1], "r");
output = fopen("output.c", "w");


        for(i = 0; ch != EOF; i++)
                                {
                                Check();

                                                                if(ch == '/')
                                                                {
                                                                Print();
                                                                EndofComment();
                                                                }
                               
                                                                if(ch == 'i')
                                                                {
                                                                MainCheck();
                                                                }
                                                               
                                                                if(a > 0)
                                                                {
                                                                        if((ch != '\n') || (ch != '\r'))
                                                                        {
                                                                        fprintf(output, "\n");
                                                                        a--;
                                                                        }
                                                                }
                                                                if(ch=='{')
                                                                {
                                                                a++;
                                                                }
                                                                if((ch=='}')&&(c != 0))
                                                                {
                                                                fprintf(output, "\n");
                                                                a--;
                                                                }
                                                               
                                                                if(ch == ';')
                                                                {
                                                                c++;
                                                                }else{
                                                                c = 0;
                                                                }

                                Print();
                                                                                                                       

                                }

fclose(input);
fclose(output);

return 0;
}

---

I can't help but think I'm going about it in the wrong way. I'm currently reading it character by character but what I need to be able to do is see what the character before and after it is to impose my rules.

Thanks in Advance.

Here are my comments to what you have so far.

1) Comment it
2) Fix the indentation

Then, I'll consider looking at it.

Your indentation program --- needs much better indentation. :p :p

There is a program called "astyle" that already does this, btw.

For a program that needs to react to the text it's importing, it's almost always better to pull in a whole row of text at a time, using fgets(). Then use sscanf() on the char buffer which now holds the line of text:

Code:

---

while((fgets(buffer, sizeof(buffer), filePointer) != NULL) { //reads all data in the file,row by row
  //rest of your code in here
  sscanf(buffer, "%d %s, %c", &myNumberVar, mystringVar, &mycharVar); //e.g
}

---

There is no overflow problem (it's safe). Make char buffer[about 80 char's].

Joy abounds. :D

Quote:

---

Originally Posted by Adak

There is no overflow problem (it's safe). Make char buffer[about 80 char's].

---

Just a thought... 80 characters might not be enough. I typically work on 100 character margins in my IDE and I've seen people using up to 128... Perhaps 256 would make more sense, the extra is a small price to pay to eliminate the risk.

Thank for all that pointers.

Sorry the indentation is so bad, its not normally its just been a case of deleting and restarting and I work in Notepad++ then copy it over to the server via Putty and lots of the formatting is lost.


Someone mentioned in an earlier thread "dont use global variables thats noob stuff", now I am a noob. Is it a global variable if you declare it before the main? What difference does it make? I only do it this way as thats the way I've been taught at school.

Second question, also we don't indent functions above the main, is that the same in the usual C programming etiquette?

Thank for the clarification, sometimes lectures just aren't enough an its good to hear the view point of others in the know.

I'll try to re-write it tommorrow using fgets() as it seems ideal because the problem with using fgetc() is that you can't compare the character before and after to apply the right rules.

Quote:

---

Originally Posted by Chems

Thank for all that pointers.

Sorry the indentation is so bad, its not normally its just been a case of deleting and restarting and I work in Notepad++ then copy it over to the server via Putty and lots of the formatting is lost.

Someone mentioned in an earlier thread "dont use global variables thats noob stuff", now I am a noob. Is it a global variable if you declare it before the main? What difference does it make? I only do it this way as thats the way I've been taught at school.

---

Yes, global variables are the one's you see above the main function. And yes, they're for noobs, in general. They're only for struct and function prototypes, and occasionally, a variable that is used in (almost) every single function.

Why are they bad? It breaks the encapsulation of the functions, adds to the potential for much harder to understand logic, and increases the likelihood that a local variable will wind up with the same name as one of the global variables - "covering up" the global version of the varriable. First time you see that, you'll swear your compiler has gone insane. :p

The purpose of functions is to "break down" the functionality of a program, into smaller "chunks". Global variables, aside from definitions, chip away at that concept.

Quote:

---

Originally Posted by Chems

Second question, also we don't indent functions above the main, is that the same in the usual C programming etiquette?

---

Yes, indentation starts with the first line of code that is subordinate:

Code:

---

int main(void) {
  //first subordinate line of code
  int i, j, n; //i,j, and n are totally encapsulated, in function main
 

  //last subordinate line of code
  return 0; //returning to the OS
}

---

Quote:

---

Originally Posted by Chems

Thank for the clarification, sometimes lectures just aren't enough an its good to hear the view point of others in the know.

I'll try to re-write it tommorrow using fgets() as it seems ideal because the problem with using fgetc() is that you can't compare the character before and after to apply the right rules.

---

You'll like fgets() once you see what it can do.

Thank Adat, very informative. I will try to stop using global variables from now on!

First off, thanks for putting me onto fgets, it so easy to use a few of the strings library functions to check for all the things that were such a hassle before.

I'm nearly there now but I want to be able to do the output like before. So my question is this,

Although I'm reading the input line by line, how do I input a character into the output string once the function has given me a pointer for instance:

Code:

---

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

int main(int argc, char *argv[])
{
        FILE *input;
        FILE *output;
        char line[256];
        int ptr;
        output = fopen("output.c", "w");

                if((input = fopen(argv[1], "r")) != NULL )
                {
                        while(fgets(line, 256, input) != NULL)
                        {
                                                                                               
                                fprintf(output, "%s", line);
                                               
                                        char *ptr = strchr(line, '{');
                       
                                                if(ptr)
                                                        {
                                                          /*Code here to insert \n after the { in the string*/
                                                        }

                        }
                }

fclose(input);
fclose(output);

}

---

TIA, and I hope the indentation is better an the use of non global variables.

Well I think it's a mistake to immediately output the input like that. You have no idea if it's well formed or not.

As for indentation, you basically need to know what level you're going into. Then you can dump the line that opens the block like

fprintf(output, "%s\n", statement);