string.c: Fix typos in comment.
[paraslash.git] / color.c
1 /** \file color.c Functions for printing colored messages. */
2
3 /*
4 * Mostly taken from the git source tree, version 1.6.1.76, January 2009.
5 */
6
7 #include "para.h"
8 #include "color.h"
9
10 static int parse_color(const char *name, int len)
11 {
12 static const char * const color_names[] = {
13 "normal", "black", "red", "green", "yellow",
14 "blue", "magenta", "cyan", "white"
15 };
16 char *end;
17 int i;
18 for (i = 0; i < ARRAY_SIZE(color_names); i++) {
19 const char *str = color_names[i];
20 if (!strncasecmp(name, str, len) && !str[len])
21 return i - 1;
22 }
23 i = strtol(name, &end, 10);
24 if (end - name == len && i >= -1 && i <= 255)
25 return i;
26 return -2;
27 }
28
29 static int parse_attr(const char *name, int len)
30 {
31 static const int attr_values[] = { 1, 2, 4, 5, 7 };
32 static const char * const attr_names[] = {
33 "bold", "dim", "ul", "blink", "reverse"
34 };
35 int i;
36 for (i = 0; i < ARRAY_SIZE(attr_names); i++) {
37 const char *str = attr_names[i];
38 if (!strncasecmp(name, str, len) && !str[len])
39 return attr_values[i];
40 }
41 return -1;
42 }
43
44 /**
45 * Create an escape sequence for colored output.
46 *
47 * \param value Human-readable color spec.
48 * \param dst Result pointer for the escape sequence.
49 *
50 * Format of \a value: [fg [bg]] [attr].
51 */
52 void color_parse_or_die(const char *value, char *dst)
53 {
54 const char *ptr = value;
55 int attr = -1;
56 int fg = -2;
57 int bg = -2;
58
59 if (!strcasecmp(value, "reset")) {
60 strcpy(dst, COLOR_RESET);
61 return;
62 }
63
64 /* [fg [bg]] [attr] */
65 while (*ptr) {
66 const char *word = ptr;
67 int val, len = 0;
68
69 while (word[len] && !para_isspace(word[len]))
70 len++;
71
72 ptr = word + len;
73 while (*ptr && para_isspace(*ptr))
74 ptr++;
75
76 val = parse_color(word, len);
77 if (val >= -1) {
78 if (fg == -2) {
79 fg = val;
80 continue;
81 }
82 if (bg == -2) {
83 bg = val;
84 continue;
85 }
86 goto bad;
87 }
88 val = parse_attr(word, len);
89 if (val < 0 || attr != -1)
90 goto bad;
91 attr = val;
92 }
93
94 if (attr >= 0 || fg >= 0 || bg >= 0) {
95 int sep = 0;
96
97 *dst++ = '\033';
98 *dst++ = '[';
99 if (attr >= 0) {
100 *dst++ = '0' + attr;
101 sep++;
102 }
103 if (fg >= 0) {
104 if (sep++)
105 *dst++ = ';';
106 if (fg < 8) {
107 *dst++ = '3';
108 *dst++ = '0' + fg;
109 } else {
110 dst += sprintf(dst, "38;5;%d", fg);
111 }
112 }
113 if (bg >= 0) {
114 if (sep)
115 *dst++ = ';';
116 if (bg < 8) {
117 *dst++ = '4';
118 *dst++ = '0' + bg;
119 } else {
120 dst += sprintf(dst, "48;5;%d", bg);
121 }
122 }
123 *dst++ = 'm';
124 }
125 *dst = 0;
126 return;
127 bad:
128 PARA_EMERG_LOG("bad color value '%s'\n", value);
129 exit(EXIT_FAILURE);
130 }