Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/less/less/../position.c	Lines:	50	59	84.7 %
Date:	2017-11-13	Branches:	31	38	81.6 %


/*
 * Copyright (C) 1984-2012  Mark Nudelman
 * Modified for use with illumos by Garrett D'Amore.
 * Copyright 2014 Garrett D'Amore <garrett@damore.org>
 *
 * You may distribute under the terms of either the GNU General Public
 * License or the Less License, as specified in the README file.
 *
 * For more information, see the README file.
 */

/*
 * Routines dealing with the "position" table.
 * This is a table which tells the position (in the input file) of the
 * first char on each currently displayed line.
 *
 * {{ The position table is scrolled by moving all the entries.
 * Would be better to have a circular table
 * and just change a couple of pointers. }}
 */

#include "less.h"
#include "position.h"

static off_t *table = NULL;	/* The position table */
static int table_size;

extern int sc_width, sc_height;

/*
 * Return the starting file position of a line displayed on the screen.
 * The line may be specified as a line number relative to the top
 * of the screen, but is usually one of these special cases:
 *	the top (first) line on the screen
 *	the second line on the screen
 *	the bottom line on the screen
 *	the line after the bottom line on the screen
 */
off_t
position(int where)
{
	switch (where) {
	case BOTTOM:
		where = sc_height - 2;
		break;
	case BOTTOM_PLUS_ONE:
		where = sc_height - 1;
		break;
	case MIDDLE:
		where = (sc_height - 1) / 2;
	}
	return (table[where]);
}

/*
 * Add a new file position to the bottom of the position table.
 */
void
add_forw_pos(off_t pos)
{
	int i;

	/*
	 * Scroll the position table up.
	 */
	for (i = 1; i < sc_height; i++)
		table[i-1] = table[i];
	table[sc_height - 1] = pos;
}

/*
 * Add a new file position to the top of the position table.
 */
void
add_back_pos(off_t pos)
{
	int i;

	/*
	 * Scroll the position table down.
	 */
	for (i = sc_height - 1; i > 0; i--)
		table[i] = table[i-1];
	table[0] = pos;
}

/*
 * Initialize the position table, done whenever we clear the screen.
 */
void
pos_clear(void)
{
	int i;

	for (i = 0; i < sc_height; i++)
		table[i] = -1;
}

/*
 * Allocate or reallocate the position table.
 */
void
pos_init(void)
{
	struct scrpos scrpos;

	if (sc_height <= table_size)
		return;
	/*
	 * If we already have a table, remember the first line in it
	 * before we free it, so we can copy that line to the new table.
	 */
	if (table != NULL) {
		get_scrpos(&scrpos);
		free(table);
	} else {
		scrpos.pos = -1;
	}
	table = ecalloc(sc_height, sizeof (off_t));
	table_size = sc_height;
	pos_clear();
	if (scrpos.pos != -1)
		table[scrpos.ln-1] = scrpos.pos;
}

/*
 * See if the byte at a specified position is currently on the screen.
 * Check the position table to see if the position falls within its range.
 * Return the position table entry if found, -1 if not.
 */
int
onscreen(off_t pos)
{
	int i;

	if (pos < table[0])
		return (-1);
	for (i = 1; i < sc_height; i++)
		if (pos < table[i])
			return (i-1);
	return (-1);
}

/*
 * See if the entire screen is empty.
 */
int
empty_screen(void)
{
	return (empty_lines(0, sc_height-1));
}

int
empty_lines(int s, int e)
{
	int i;

	for (i = s; i <= e; i++)
		if (table[i] != -1 && table[i] != 0)
			return (0);
	return (1);
}

/*
 * Get the current screen position.
 * The screen position consists of both a file position and
 * a screen line number where the file position is placed on the screen.
 * Normally the screen line number is 0, but if we are positioned
 * such that the top few lines are empty, we may have to set
 * the screen line to a number > 0.
 */
void
get_scrpos(struct scrpos *scrpos)
{
	int i;

	/*
	 * Find the first line on the screen which has something on it,
	 * and return the screen line number and the file position.
	 */
	for (i = 0; i < sc_height; i++)
		if (table[i] != -1) {
			scrpos->ln = i+1;
			scrpos->pos = table[i];
			return;
		}
	/*
	 * The screen is empty.
	 */
	scrpos->pos = -1;
}

/*
 * Adjust a screen line number to be a simple positive integer
 * in the range { 0 .. sc_height-2 }.
 * (The bottom line, sc_height-1, is reserved for prompts, etc.)
 * The given "sline" may be in the range { 1 .. sc_height-1 }
 * to refer to lines relative to the top of the screen (starting from 1),
 * or it may be in { -1 .. -(sc_height-1) } to refer to lines
 * relative to the bottom of the screen.
 */
int
adjsline(int sline)
{
	/*
	 * Negative screen line number means
	 * relative to the bottom of the screen.
	 */
	if (sline < 0)
		sline += sc_height;
	/*
	 * Can't be less than 1 or greater than sc_height-1.
	 */
	if (sline <= 0)
		sline = 1;
	if (sline >= sc_height)
		sline = sc_height - 1;
	/*
	 * Return zero-based line number, not one-based.
	 */
	return (sline-1);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/*
2			* Copyright (C) 1984-2012 Mark Nudelman
3			* Modified for use with illumos by Garrett D'Amore.
4			* Copyright 2014 Garrett D'Amore <garrett@damore.org>
5			*
6			* You may distribute under the terms of either the GNU General Public
7			* License or the Less License, as specified in the README file.
8			*
9			* For more information, see the README file.
10			*/
11
12			/*
13			* Routines dealing with the "position" table.
14			* This is a table which tells the position (in the input file) of the
15			* first char on each currently displayed line.
16			*
17			* {{ The position table is scrolled by moving all the entries.
18			* Would be better to have a circular table
19			* and just change a couple of pointers. }}
20			*/
21
22			#include "less.h"
23			#include "position.h"
24
25			static off_t table = NULL; / The position table */
26			static int table_size;
27
28			extern int sc_width, sc_height;
29
30			/*
31			* Return the starting file position of a line displayed on the screen.
32			* The line may be specified as a line number relative to the top
33			* of the screen, but is usually one of these special cases:
34			* the top (first) line on the screen
35			* the second line on the screen
36			* the bottom line on the screen
37			* the line after the bottom line on the screen
38			*/
39			off_t
40			position(int where)
41			{
42	✓✓✗✓	989	switch (where) {
43			case BOTTOM:
44		35	where = sc_height - 2;
45		35	break;
46			case BOTTOM_PLUS_ONE:
47		148	where = sc_height - 1;
48		148	break;
49			case MIDDLE:
50			where = (sc_height - 1) / 2;
51			}
52		403	return (table[where]);
53			}
54
55			/*
56			* Add a new file position to the bottom of the position table.
57			*/
58			void
59			add_forw_pos(off_t pos)
60			{
61			int i;
62
63			/*
64			* Scroll the position table up.
65			*/
66	✓✓	53935	for (i = 1; i < sc_height; i++)
67		25760	table[i-1] = table[i];
68		805	table[sc_height - 1] = pos;
69		805	}
70
71			/*
72			* Add a new file position to the top of the position table.
73			*/
74			void
75			add_back_pos(off_t pos)
76			{
77			int i;
78
79			/*
80			* Scroll the position table down.
81			*/
82	✓✓	15008	for (i = sc_height - 1; i > 0; i--)
83		7168	table[i] = table[i-1];
84		224	table[0] = pos;
85		224	}
86
87			/*
88			* Initialize the position table, done whenever we clear the screen.
89			*/
90			void
91			pos_clear(void)
92			{
93			int i;
94
95	✓✓	3864	for (i = 0; i < sc_height; i++)
96		1848	table[i] = -1;
97		56	}
98
99			/*
100			* Allocate or reallocate the position table.
101			*/
102			void
103			pos_init(void)
104			{
105		16	struct scrpos scrpos;
106
107	✗✓	8	if (sc_height <= table_size)
108			return;
109			/*
110			* If we already have a table, remember the first line in it
111			* before we free it, so we can copy that line to the new table.
112			*/
113	✗✓	8	if (table != NULL) {
114			get_scrpos(&scrpos);
115			free(table);
116			} else {
117		8	scrpos.pos = -1;
118			}
119		8	table = ecalloc(sc_height, sizeof (off_t));
120		8	table_size = sc_height;
121		8	pos_clear();
122	✗✓	8	if (scrpos.pos != -1)
123			table[scrpos.ln-1] = scrpos.pos;
124		16	}
125
126			/*
127			* See if the byte at a specified position is currently on the screen.
128			* Check the position table to see if the position falls within its range.
129			* Return the position table entry if found, -1 if not.
130			*/
131			int
132			onscreen(off_t pos)
133			{
134			int i;
135
136	✗✓	32	if (pos < table[0])
137			return (-1);
138	✓✓	1000	for (i = 1; i < sc_height; i++)
139	✓✓	485	if (pos < table[i])
140		1	return (i-1);
141		15	return (-1);
142		16	}
143
144			/*
145			* See if the entire screen is empty.
146			*/
147			int
148			empty_screen(void)
149			{
150		142	return (empty_lines(0, sc_height-1));
151			}
152
153			int
154			empty_lines(int s, int e)
155			{
156			int i;
157
158	✓✓	2455	for (i = s; i <= e; i++)
159	✓✓✓✓	1206	if (table[i] != -1 && table[i] != 0)
160		54	return (0);
161		45	return (1);
162		99	}
163
164			/*
165			* Get the current screen position.
166			* The screen position consists of both a file position and
167			* a screen line number where the file position is placed on the screen.
168			* Normally the screen line number is 0, but if we are positioned
169			* such that the top few lines are empty, we may have to set
170			* the screen line to a number > 0.
171			*/
172			void
173			get_scrpos(struct scrpos *scrpos)
174			{
175			int i;
176
177			/*
178			* Find the first line on the screen which has something on it,
179			* and return the screen line number and the file position.
180			*/
181	✓✓	1113	for (i = 0; i < sc_height; i++)
182	✓✓	521	if (table[i] != -1) {
183		26	scrpos->ln = i+1;
184		26	scrpos->pos = table[i];
185		26	return;
186			}
187			/*
188			* The screen is empty.
189			*/
190		15	scrpos->pos = -1;
191		56	}
192
193			/*
194			* Adjust a screen line number to be a simple positive integer
195			* in the range { 0 .. sc_height-2 }.
196			* (The bottom line, sc_height-1, is reserved for prompts, etc.)
197			* The given "sline" may be in the range { 1 .. sc_height-1 }
198			* to refer to lines relative to the top of the screen (starting from 1),
199			* or it may be in { -1 .. -(sc_height-1) } to refer to lines
200			* relative to the bottom of the screen.
201			*/
202			int
203			adjsline(int sline)
204			{
205			/*
206			* Negative screen line number means
207			* relative to the bottom of the screen.
208			*/
209	✗✓	38	if (sline < 0)
210			sline += sc_height;
211			/*
212			* Can't be less than 1 or greater than sc_height-1.
213			*/
214	✓✓	19	if (sline <= 0)
215		4	sline = 1;
216	✗✓	19	if (sline >= sc_height)
217			sline = sc_height - 1;
218			/*
219			* Return zero-based line number, not one-based.
220			*/
221		19	return (sline-1);
222			}