aboutsummaryrefslogtreecommitdiffstats
path: root/common/pango.c
blob: 18b92e9d3b79a228584d8b91bde14aaf3771196f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
#include <cairo/cairo.h>
#include <pango/pangocairo.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "cairo.h"
#include "log.h"
#include "stringop.h"

static const char overflow[] = "[buffer overflow]";
static const int max_chars = 16384;

size_t escape_markup_text(const char *src, char *dest) {
	size_t length = 0;
	if (dest) {
		dest[0] = '\0';
	}

	while (src[0]) {
		switch (src[0]) {
		case '&':
			length += 5;
			lenient_strcat(dest, "&amp;");
			break;
		case '<':
			length += 4;
			lenient_strcat(dest, "&lt;");
			break;
		case '>':
			length += 4;
			lenient_strcat(dest, "&gt;");
			break;
		case '\'':
			length += 6;
			lenient_strcat(dest, "&apos;");
			break;
		case '"':
			length += 6;
			lenient_strcat(dest, "&quot;");
			break;
		default:
			if (dest) {
				dest[length] = *src;
				dest[length + 1] = '\0';
			}
			length += 1;
		}
		src++;
	}
	return length;
}

PangoLayout *get_pango_layout(cairo_t *cairo, const char *font,
		const char *text, double scale, bool markup) {
	PangoLayout *layout = pango_cairo_create_layout(cairo);
	PangoAttrList *attrs;
	if (markup) {
		char *buf;
		GError *error = NULL;
		if (pango_parse_markup(text, -1, 0, &attrs, &buf, NULL, &error)) {
			pango_layout_set_text(layout, buf, -1);
			free(buf);
		} else {
			wlr_log(WLR_ERROR, "pango_parse_markup '%s' -> error %s", text,
					error->message);
			g_error_free(error);
			markup = false; // fallback to plain text
		}
	}
	if (!markup) {
		attrs = pango_attr_list_new();
		pango_layout_set_text(layout, text, -1);
	}

	pango_attr_list_insert(attrs, pango_attr_scale_new(scale));
	PangoFontDescription *desc = pango_font_description_from_string(font);
	pango_layout_set_font_description(layout, desc);
	pango_layout_set_single_paragraph_mode(layout, 1);
	pango_layout_set_attributes(layout, attrs);
	pango_attr_list_unref(attrs);
	pango_font_description_free(desc);
	return layout;
}

void get_text_size(cairo_t *cairo, const char *font, int *width, int *height,
		int *baseline, double scale, bool markup, const char *fmt, ...) {
	char *buf = malloc(sizeof(char) * max_chars);

	va_list args;
	va_start(args, fmt);
	if (vsnprintf(buf, sizeof(char) * max_chars, fmt, args) >= max_chars) {
		strcpy(&buf[sizeof(buf) - sizeof(overflow)], overflow);
	}
	va_end(args);

	PangoLayout *layout = get_pango_layout(cairo, font, buf, scale, markup);
	pango_cairo_update_layout(cairo, layout);
	pango_layout_get_pixel_size(layout, width, height);
	if (baseline) {
		*baseline = pango_layout_get_baseline(layout) / PANGO_SCALE;
	}
	g_object_unref(layout);

	free(buf);
}

void pango_printf(cairo_t *cairo, const char *font,
		double scale, bool markup, const char *fmt, ...) {
	char *buf = malloc(sizeof(char) * max_chars);

	va_list args;
	va_start(args, fmt);
	if (vsnprintf(buf, sizeof(char) * max_chars, fmt, args) >= max_chars) {
		strcpy(&buf[sizeof(buf) - sizeof(overflow)], overflow);
	}
	va_end(args);

	PangoLayout *layout = get_pango_layout(cairo, font, buf, scale, markup);
	cairo_font_options_t *fo = cairo_font_options_create();
	cairo_get_font_options(cairo, fo);
	pango_cairo_context_set_font_options(pango_layout_get_context(layout), fo);
	cairo_font_options_destroy(fo);
	pango_cairo_update_layout(cairo, layout);
	pango_cairo_show_layout(cairo, layout);
	g_object_unref(layout);

	free(buf);
}