/* Utility functions definitions */

#ifndef SYSTEM_H_
#define SYSTEM_H_

#include <stddef.h>
#include <stdio.h>
#include <limits.h>
#include <stdint.h>
#include <string.h>

#ifdef __cplusplus
#define SYSTEM_H_BEGIN_ extern "C" {
#define SYSTEM_H_END_ }
#else
#define SYSTEM_H_BEGIN_
#define SYSTEM_H_END_
#endif

SYSTEM_H_BEGIN_

#ifndef __MINGW32__
#define DGEN_BASEDIR ".dgen"
#define DGEN_RC "dgenrc"
#define DGEN_AUTORC "dgenrc.auto"
#define DGEN_DIRSEP "/"
#else
#define DGEN_BASEDIR "DGen"
#define DGEN_RC "dgen.cfg"
#define DGEN_AUTORC "dgen_auto.cfg"
#define DGEN_DIRSEP "\\/"
#endif

#define elemof(a) (sizeof(a) / sizeof((a)[0]))
#define containerof(p, s, m) (s *)((uintptr_t)(p) - offsetof(s, m))

#define BITS_TO_BYTES(v) ((((v) + 7u) & ~7u) >> 3)

#define DGEN_READ 0x1
#define DGEN_WRITE 0x2
#define DGEN_APPEND 0x4
#define DGEN_CURRENT 0x8
#define DGEN_TEXT 0x10

#define dgen_fopen_rc(mode) dgen_fopen(NULL, DGEN_RC, ((mode) | DGEN_TEXT))
#define dgen_fopen_autorc(mode)					\
	dgen_fopen(NULL, DGEN_AUTORC, ((mode) | DGEN_TEXT))
extern FILE *dgen_fopen(const char *relative, const char *file,
			unsigned int mode);
extern FILE *dgen_freopen(const char *relative, const char *file,
			  unsigned int mode, FILE *f);
extern const char *dgen_basename(const char *path);
extern char *dgen_dir(char *buf, size_t *size, const char *sub);
extern char *dgen_userdir(char *buf, size_t *size);

#define le2h16(v) h2le16(v)
static inline uint16_t h2le16(uint16_t v)
{
#ifdef WORDS_BIGENDIAN
	return ((v >> 8) | (v << 8));
#else
	return v;
#endif
}

#define be2h16(v) h2be16(v)
static inline uint16_t h2be16(uint16_t v)
{
#ifdef WORDS_BIGENDIAN
	return v;
#else
	return ((v >> 8) | (v << 8));
#endif
}

#define le2h32(v) h2le32(v)
static inline uint32_t h2le32(uint32_t v)
{
#ifdef WORDS_BIGENDIAN
	return (((v & 0xff000000) >> 24) | ((v & 0x00ff0000) >>  8) |
		((v & 0x0000ff00) <<  8) | ((v & 0x000000ff) << 24));
#else
	return v;
#endif
}

#define be2h32(v) h2be32(v)
static inline uint32_t h2be32(uint32_t v)
{
#ifdef WORDS_BIGENDIAN
	return v;
#else
	return (((v & 0xff000000) >> 24) | ((v & 0x00ff0000) >>  8) |
		((v & 0x0000ff00) <<  8) | ((v & 0x000000ff) << 24));
#endif
}

typedef uint8_t uint24_t[3];

static inline uint24_t *u24cpy(uint24_t *dst, const uint24_t *src)
{
	/* memcpy() is sometimes faster. */
#ifdef U24CPY_MEMCPY
	memcpy(*dst, *src, sizeof(*dst));
#else
	(*dst)[0] = (*src)[0];
	(*dst)[1] = (*src)[1];
	(*dst)[2] = (*src)[2];
#endif
	return dst;
}

extern uint8_t *load(void **context,
		     size_t *file_size, FILE *file, size_t max_size);
extern void load_finish(void **context);
extern void unload(uint8_t *data);

extern char **complete_path(const char *prefix, size_t len,
			    const char *relative);
extern void complete_path_free(char **cp);

static inline size_t strcommon(const char *s1, const char *s2)
{
	size_t i;

	for (i = 0; ((s1[i] != '\0') && (s2[i] != '\0')); ++i)
		if (s1[i] != s2[i])
			break;
	return i;
}

#define BACKSLASHIFY_NOQUOTES 0x0001

extern char *backslashify(const uint8_t *src, size_t size, unsigned int flags,
			  size_t *pos);

extern size_t utf8u32(uint32_t *u32, const uint8_t *u8);
extern size_t utf32u8(uint8_t *u8, uint32_t u32);

extern int prefix_casematch(const char *str, const char *argv[]);
extern size_t prefix_getuint(const char *str, unsigned int *num);

SYSTEM_H_END_

#endif /* SYSTEM_H_ */