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

#include "inotify_helpers.h"

static
const char *in_bits[] = {
	/* main */
	"IN_ACCESS",	// 0
	"IN_MODIFY",	// 1
	"IN_ATTRIB",	// 2
	"IN_CLOSE_WRITE",	// 3
	"IN_CLOSE_NOWRITE",	// 4
	"IN_OPEN",	// 5
	"IN_MOVED_FROM",	// 6
	"IN_MOVED_TO",	// 7
	"IN_CREATE",	// 8
	"IN_DELETE",	// 9
	"IN_DELETE_SELF",	// 10
	"IN_MOVE_SELF",	// 11
	/* gap */
	"<invalid-12>",	// 12
	/* events sent by the kernel */
	"IN_UNMOUNT",	// 13
	"IN_Q_OVERFLOW",	// 14
	"IN_IGNORED",	// 15
	/* gap */
	"<invalid-16>",	// 16
	"<invalid-17>",	// 17
	"<invalid-18>",	// 18
	"<invalid-19>",	// 19
	"<invalid-20>",	// 20
	"<invalid-21>",	// 21
	"<invalid-22>",	// 22
	"<invalid-23>",	// 23
	/* special flags */
	"IN_ONLYDIR",	// 24
	"IN_DONT_FOLLOW",	// 25
	"IN_EXCL_UNLINK",	// 26
	"<invalid-27>",	// 27
	"<invalid-28>",	// 28
	"IN_MASK_ADD",	// 29
	"IN_ISDIR",	// 30
	"IN_ONESHOT",	// 31
};

char *inotify_mask2str(uint32 mask);
int inotify_print_event(FILE *file, struct inotify_event *event);


struct strbuf {
	char *str; 
	size_t len;
	size_t cap;
};

static
void strbufcat(struct strbuf *a, const char *b) {
	size_t blen = strlen(b);
	while (a->cap <= (a->len + blen)) {
		a->cap += 256;
		a->str = realloc(a->str, a->cap);
	}
	memcpy(&(a->str[a->len]), b, blen+1);
	a->len += blen;
}


char *inotify_mask2str(uint32_t mask) {
	struct strbuf out = { NULL, 0, 0 };
	for (size_t i = 0; i < sizeof(in_bits)/sizeof(in_bits[0]); i++) {
		if (mask & (1 << i)) {
			if (out.len > 0)
				strbufcat(&out, ", ");
			strbufcat(&out, in_bits[i]);
		}
	}
	return out.str;
}

int inotify_print_event(struct inotify_event *event) {
	return printf("wd:%d\n"
	              "\tmask:[%s]\n"
	              "\tcookie:%u\n"
	              "\tlen:%u\n"
	              "\tname:%s\n",
	              event->wd,
	              mask2str(event->mask),
	              event->cookie,
	              event->len,
	              event->len > 0 ? event->name : "");
}