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/*
	index: frame index data structure and functions
 
	copyright 2007-8 by the mpg123 project - free software under the terms of the LGPL 2.1
	see COPYING and AUTHORS files in distribution or http://mpg123.org
	initially written by Thomas Orgis
*/
 
#include "index.h"
#include "debug.h"
 
/* The next expected frame offset, one step ahead. */
static off_t fi_next(struct frame_index *fi)
{
	return (off_t)fi->fill*fi->step;
}
 
/* Shrink down the used index to the half.
   Be careful with size = 1 ... there's no shrinking possible there. */
static void fi_shrink(struct frame_index *fi)
{
	if(fi->fill < 2) return; /* Won't shrink below 1. */
	else
	{ /* Double the step, half the fill. Should work as well for fill%2 = 1 */
		size_t c;
		debug2("shrink index with fill %lu and step %lu", (unsigned long)fi->fill, (unsigned long)fi->step);
		fi->step *= 2;
		fi->fill /= 2;
		/* Move the data down. */
		for(c = 0; c < fi->fill; ++c)
		fi->data[c] = fi->data[2*c];
	}
 
	fi->next = fi_next(fi);
}
 
void fi_init(struct frame_index *fi)
{
	fi->data = NULL;
	fi->step = 1;
	fi->fill = 0;
	fi->size = 0;
	fi->grow_size = 0;
	fi->next = fi_next(fi);
}
 
void fi_exit(struct frame_index *fi)
{
	debug2("fi_exit: %p and %lu", (void*)fi->data, (unsigned long)fi->size);
	if(fi->size && fi->data != NULL) free(fi->data);
 
	fi_init(fi); /* Be prepared for further fun, still. */
}
 
int fi_resize(struct frame_index *fi, size_t newsize)
{
	off_t *newdata = NULL;
	if(newsize == fi->size) return 0;
 
	if(newsize > 0 && newsize < fi->size)
	{ /* When we reduce buffer size a bit, shrink stuff. */
		while(fi->fill > newsize){ fi_shrink(fi); }
	}
 
	newdata = safe_realloc(fi->data, newsize*sizeof(off_t));
	if(newsize == 0 || newdata != NULL)
	{
		fi->data = newdata;
		fi->size = newsize;
		if(fi->fill > fi->size) fi->fill = fi->size;
 
		fi->next = fi_next(fi);
		debug2("new index of size %lu at %p", (unsigned long)fi->size, (void*)fi->data);
		return 0;
	}
	else
	{
		error("failed to resize index!");
		return -1;
	}
}
 
void fi_add(struct frame_index *fi, off_t pos)
{
	debug3("wanting to add to fill %lu, step %lu, size %lu", (unsigned long)fi->fill, (unsigned long)fi->step, (unsigned long)fi->size);
	if(fi->fill == fi->size)
	{ /* Index is full, we need to shrink... or grow. */
		/* Store the current frame number to check later if we still want it. */
		off_t framenum = fi->fill*fi->step;
		/* If we want not / cannot grow, we shrink. */	
		if( !(fi->grow_size && fi_resize(fi, fi->size+fi->grow_size)==0) )
		fi_shrink(fi);
 
		/* Now check if we still want to add this frame (could be that not, because of changed step). */
		if(fi->next != framenum) return;
	}
	/* When we are here, we want that frame. */
	if(fi->fill < fi->size) /* safeguard for size=1, or just generally */
	{
		debug1("adding to index at %p", (void*)(fi->data+fi->fill));
		fi->data[fi->fill] = pos;
		++fi->fill;
		fi->next = fi_next(fi);
		debug3("added pos %li to index with fill %lu and step %lu", (long) pos, (unsigned long)fi->fill, (unsigned long)fi->step);
	}
}
 
int fi_set(struct frame_index *fi, off_t *offsets, off_t step, size_t fill)
{
	if(fi_resize(fi, fill) == -1) return -1;
	fi->step = step;
	if(offsets != NULL)
	{
		memcpy(fi->data, offsets, fill*sizeof(off_t));
		fi->fill = fill;
	}
	else
	{
		/* allocation only, no entries in index yet */
		fi->fill = 0;
	}
	fi->next = fi_next(fi);
	debug3("set new index of fill %lu, size %lu at %p",
	(unsigned long)fi->fill, (unsigned long)fi->size, (void*)fi->data);
	return 0;
}
 
void fi_reset(struct frame_index *fi)
{
	debug1("reset with size %"SIZE_P, (size_p)fi->size);
	fi->fill = 0;
	fi->step = 1;
	fi->next = fi_next(fi);
}

Rev 1905	Rev 3960
1	/*	1	/*
2	index: frame index data structure and functions	2	index: frame index data structure and functions
3		3
4	copyright 2007-8 by the mpg123 project - free software under the terms of the LGPL 2.1	4	copyright 2007-8 by the mpg123 project - free software under the terms of the LGPL 2.1
5	see COPYING and AUTHORS files in distribution or http://mpg123.org	5	see COPYING and AUTHORS files in distribution or http://mpg123.org
6	initially written by Thomas Orgis	6	initially written by Thomas Orgis
7	*/	7	*/
8		8
9	#include "index.h"	9	#include "index.h"
10	#include "debug.h"	10	#include "debug.h"
11		11
12	/* The next expected frame offset, one step ahead. */	12	/* The next expected frame offset, one step ahead. */
13	static off_t fi_next(struct frame_index *fi)	13	static off_t fi_next(struct frame_index *fi)
14	{	14	{
15	return (off_t)fi->fill*fi->step;	15	return (off_t)fi->fill*fi->step;
16	}	16	}
17		17
18	/* Shrink down the used index to the half.	18	/* Shrink down the used index to the half.
19	Be careful with size = 1 ... there's no shrinking possible there. */	19	Be careful with size = 1 ... there's no shrinking possible there. */
20	static void fi_shrink(struct frame_index *fi)	20	static void fi_shrink(struct frame_index *fi)
21	{	21	{
22	if(fi->fill < 2) return; /* Won't shrink below 1. */	22	if(fi->fill < 2) return; /* Won't shrink below 1. */
23	else	23	else
24	{ /* Double the step, half the fill. Should work as well for fill%2 = 1 */	24	{ /* Double the step, half the fill. Should work as well for fill%2 = 1 */
25	size_t c;	25	size_t c;
26	debug2("shrink index with fill %lu and step %lu", (unsigned long)fi->fill, (unsigned long)fi->step);	26	debug2("shrink index with fill %lu and step %lu", (unsigned long)fi->fill, (unsigned long)fi->step);
27	fi->step *= 2;	27	fi->step *= 2;
28	fi->fill /= 2;	28	fi->fill /= 2;
29	/* Move the data down. */	29	/* Move the data down. */
30	for(c = 0; c < fi->fill; ++c)	30	for(c = 0; c < fi->fill; ++c)
31	fi->data[c] = fi->data[2*c];	31	fi->data[c] = fi->data[2*c];
32	}	32	}
33		33
34	fi->next = fi_next(fi);	34	fi->next = fi_next(fi);
35	}	35	}
36		36
37	void fi_init(struct frame_index *fi)	37	void fi_init(struct frame_index *fi)
38	{	38	{
39	fi->data = NULL;	39	fi->data = NULL;
40	fi->step = 1;	40	fi->step = 1;
41	fi->fill = 0;	41	fi->fill = 0;
42	fi->size = 0;	42	fi->size = 0;
43	fi->grow_size = 0;	43	fi->grow_size = 0;
44	fi->next = fi_next(fi);	44	fi->next = fi_next(fi);
45	}	45	}
46		46
47	void fi_exit(struct frame_index *fi)	47	void fi_exit(struct frame_index *fi)
48	{	48	{
49	debug2("fi_exit: %p and %lu", (void*)fi->data, (unsigned long)fi->size);	49	debug2("fi_exit: %p and %lu", (void*)fi->data, (unsigned long)fi->size);
50	if(fi->size && fi->data != NULL) free(fi->data);	50	if(fi->size && fi->data != NULL) free(fi->data);
51		51
52	fi_init(fi); /* Be prepared for further fun, still. */	52	fi_init(fi); /* Be prepared for further fun, still. */
53	}	53	}
54		54
55	int fi_resize(struct frame_index *fi, size_t newsize)	55	int fi_resize(struct frame_index *fi, size_t newsize)
56	{	56	{
57	off_t *newdata = NULL;	57	off_t *newdata = NULL;
58	if(newsize == fi->size) return 0;	58	if(newsize == fi->size) return 0;
59		59
60	if(newsize > 0 && newsize < fi->size)	60	if(newsize > 0 && newsize < fi->size)
61	{ /* When we reduce buffer size a bit, shrink stuff. */	61	{ /* When we reduce buffer size a bit, shrink stuff. */
62	while(fi->fill > newsize){ fi_shrink(fi); }	62	while(fi->fill > newsize){ fi_shrink(fi); }
63	}	63	}
64		64
65	newdata = safe_realloc(fi->data, newsize*sizeof(off_t));	65	newdata = safe_realloc(fi->data, newsize*sizeof(off_t));
66	if(newsize == 0 \|\| newdata != NULL)	66	if(newsize == 0 \|\| newdata != NULL)
67	{	67	{
68	fi->data = newdata;	68	fi->data = newdata;
69	fi->size = newsize;	69	fi->size = newsize;
70	if(fi->fill > fi->size) fi->fill = fi->size;	70	if(fi->fill > fi->size) fi->fill = fi->size;
71		71
72	fi->next = fi_next(fi);	72	fi->next = fi_next(fi);
73	debug2("new index of size %lu at %p", (unsigned long)fi->size, (void*)fi->data);	73	debug2("new index of size %lu at %p", (unsigned long)fi->size, (void*)fi->data);
74	return 0;	74	return 0;
75	}	75	}
76	else	76	else
77	{	77	{
78	error("failed to resize index!");	78	error("failed to resize index!");
79	return -1;	79	return -1;
80	}	80	}
81	}	81	}
82		82
83	void fi_add(struct frame_index *fi, off_t pos)	83	void fi_add(struct frame_index *fi, off_t pos)
84	{	84	{
85	debug3("wanting to add to fill %lu, step %lu, size %lu", (unsigned long)fi->fill, (unsigned long)fi->step, (unsigned long)fi->size);	85	debug3("wanting to add to fill %lu, step %lu, size %lu", (unsigned long)fi->fill, (unsigned long)fi->step, (unsigned long)fi->size);
86	if(fi->fill == fi->size)	86	if(fi->fill == fi->size)
87	{ /* Index is full, we need to shrink... or grow. */	87	{ /* Index is full, we need to shrink... or grow. */
88	/* Store the current frame number to check later if we still want it. */	88	/* Store the current frame number to check later if we still want it. */
89	off_t framenum = fi->fill*fi->step;	89	off_t framenum = fi->fill*fi->step;
90	/* If we want not / cannot grow, we shrink. */	90	/* If we want not / cannot grow, we shrink. */
91	if( !(fi->grow_size && fi_resize(fi, fi->size+fi->grow_size)==0) )	91	if( !(fi->grow_size && fi_resize(fi, fi->size+fi->grow_size)==0) )
92	fi_shrink(fi);	92	fi_shrink(fi);
93		93
94	/* Now check if we still want to add this frame (could be that not, because of changed step). */	94	/* Now check if we still want to add this frame (could be that not, because of changed step). */
95	if(fi->next != framenum) return;	95	if(fi->next != framenum) return;
96	}	96	}
97	/* When we are here, we want that frame. */	97	/* When we are here, we want that frame. */
98	if(fi->fill < fi->size) /* safeguard for size=1, or just generally */	98	if(fi->fill < fi->size) /* safeguard for size=1, or just generally */
99	{	99	{
100	debug1("adding to index at %p", (void*)(fi->data+fi->fill));	100	debug1("adding to index at %p", (void*)(fi->data+fi->fill));
101	fi->data[fi->fill] = pos;	101	fi->data[fi->fill] = pos;
102	++fi->fill;	102	++fi->fill;
103	fi->next = fi_next(fi);	103	fi->next = fi_next(fi);
104	debug3("added pos %li to index with fill %lu and step %lu", (long) pos, (unsigned long)fi->fill, (unsigned long)fi->step);	104	debug3("added pos %li to index with fill %lu and step %lu", (long) pos, (unsigned long)fi->fill, (unsigned long)fi->step);
105	}	105	}
106	}	106	}
-		107
-		108	int fi_set(struct frame_index fi, off_t offsets, off_t step, size_t fill)
-		109	{
-		110	if(fi_resize(fi, fill) == -1) return -1;
-		111	fi->step = step;
-		112	if(offsets != NULL)
-		113	{
-		114	memcpy(fi->data, offsets, fill*sizeof(off_t));
-		115	fi->fill = fill;
-		116	}
-		117	else
-		118	{
-		119	/* allocation only, no entries in index yet */
-		120	fi->fill = 0;
-		121	}
-		122	fi->next = fi_next(fi);
-		123	debug3("set new index of fill %lu, size %lu at %p",
-		124	(unsigned long)fi->fill, (unsigned long)fi->size, (void*)fi->data);
-		125	return 0;
-		126	}
107		127
108	void fi_reset(struct frame_index *fi)	128	void fi_reset(struct frame_index *fi)
109	{	129	{
110	debug1("reset with size %"SIZE_P, (size_p)fi->size);	130	debug1("reset with size %"SIZE_P, (size_p)fi->size);
111	fi->fill = 0;	131	fi->fill = 0;
112	fi->step = 1;	132	fi->step = 1;
113	fi->next = fi_next(fi);	133	fi->next = fi_next(fi);
114	}	134	}

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(root)/programs/develop/libraries/libmpg123/index.c – Rev 1905 → 3960