Header files in C are painful. They duplicate file count, increase complexity, make refactoring painful. There are solutions to get rid of them. It's possible to use header generators ( https://www.hwaci.com/sw/mkhdr/ - makeheaders ), write you own headerless c dialect with a precompiler like me ( https://github.com/milgra/clc class-c ) or use "#ifdef FOO_IMPLEMENTATION" blocks inside header files to define everything in one file but they are unelegant and confusing and have a lot of other problems.
The ultimate solution seems to be using the __INCLUDE_LEVEL__ preprocessor macro. It's value is zero if we are in a source file that was added directly to the compiler as parameter and greater than zero if we are in a file that was included as a header file from an other file.
So just create a single file, write the header declarations at the top, write the implementation under that and guard the implementation with an #if __INCLUDE_LEVEL__ == 0 macro and you never have to use header files again unless you need a library interface. You can include all files written this way as header files and add these files as source files to the compiler, everything will work as before.
Example : mtvec.c
#ifndef mtvec_h
#define mtvec_h
#include <stdio.h>
#include <stdint.h>
typedef struct mtvec_t mtvec_t;
struct mtvec_t
{
void** data;
uint32_t length;
uint32_t length_real;
};
mtvec_t* mtvec_alloc(void);
void mtvec_dealloc( void* vector );
void mtvec_reset( mtvec_t* vector );
#endif
#if __INCLUDE_LEVEL__ == 0
mtvec_t* mtvec_alloc( )
{
mtvec_t* vector = mtmem_calloc( sizeof( mtvec_t ) , mtvec_dealloc );
vector->data = mtmem_calloc( sizeof( void* ) * 10 , NULL );
vector->length = 0;
vector->length_real = 10;
return vector;
}
void mtvec_dealloc( void* pointer )
{
mtvec_t* vector = pointer;
for ( uint32_t index = 0 ; index < vector->length ; index++ ) {
mtmem_release( vector->data[index] );
}
mtmem_release( vector->data );
}
void mtvec_reset( mtvec_t* vector )
{
for ( uint32_t index = 0 ; index < vector->length ; index++ ) mtmem_release( vector->data[index] );
vector->length = 0;
}
#endif
I created/maintain seven applications so far in headerless C and haven't faced any drawbacks yet, feel free to try them :
- MultiMedia File Manager (https://github.com/milgra/mmfm)
- Visual Music Player (https://github.com/milgra/vmp)
- Wayland Control Panel (https://github.com/milgra/wcp)
- Sway Overview (https://github.com/milgra/sov)
- Cortex (https://github.com/milgra/cortex)
- Termite (https://github.com/milgra/termite)
- Brawl (https://github.com/milgra/brawl)