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29 * Defived from FreeBSD head/lib/libc/gen/vis.c 165903, head/include/vis.h
33 #include <sys/types.h>
39 * to select alternate encoding format
41 #define VIS_OCTAL 0x01 /* use octal \ddd format */
42 #define VIS_CSTYLE 0x02 /* use \[nrft0..] where appropriate */
45 * to alter set of characters encoded (default is to encode all
46 * non-graphic except space, tab, and newline).
48 #define VIS_SP 0x04 /* also encode space */
49 #define VIS_TAB 0x08 /* also encode tab */
50 #define VIS_NL 0x10 /* also encode newline */
51 #define VIS_WHITE (VIS_SP | VIS_TAB | VIS_NL)
52 #define VIS_SAFE 0x20 /* only encode "unsafe" characters */
57 #define VIS_NOSLASH 0x40 /* inhibit printing '\' */
58 #define VIS_HTTPSTYLE 0x80 /* http-style escape % HEX HEX */
59 #define VIS_GLOB 0x100 /* encode glob(3) magics */
64 #define UNVIS_VALID 1 /* character valid */
65 #define UNVIS_VALIDPUSH 2 /* character valid, push back passed char */
66 #define UNVIS_NOCHAR 3 /* valid sequence, no character produced */
67 #define UNVIS_SYNBAD -1 /* unrecognized escape sequence */
68 #define UNVIS_ERROR -2 /* decoder in unknown state (unrecoverable) */
73 #define UNVIS_END 1 /* no more characters */
75 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
78 * vis - visually encode characters
81 vis(dst, c, flag, nextc)
88 if (flag & VIS_HTTPSTYLE) {
89 /* Described in RFC 1808 */
90 if (!(isalnum(c) /* alpha-numeric */
92 || c == '$' || c == '-' || c == '_' || c == '.' || c == '+'
94 || c == '!' || c == '*' || c == '\'' || c == '('
95 || c == ')' || c == ',')) {
97 snprintf(dst, 4, (c < 16 ? "0%X" : "%X"), c);
103 if ((flag & VIS_GLOB) &&
104 (c == '*' || c == '?' || c == '[' || c == '#'))
106 else if (isgraph(c) ||
107 ((flag & VIS_SP) == 0 && c == ' ') ||
108 ((flag & VIS_TAB) == 0 && c == '\t') ||
109 ((flag & VIS_NL) == 0 && c == '\n') ||
110 ((flag & VIS_SAFE) && (c == '\b' || c == '\007' || c == '\r'))) {
112 if (c == '\\' && (flag & VIS_NOSLASH) == 0)
118 if (flag & VIS_CSTYLE) {
155 if (isoctal(nextc)) {
162 if (((c & 0177) == ' ') || isgraph(c) || (flag & VIS_OCTAL)) {
164 *dst++ = ((u_char)c >> 6 & 07) + '0';
165 *dst++ = ((u_char)c >> 3 & 07) + '0';
166 *dst++ = ((u_char)c & 07) + '0';
169 if ((flag & VIS_NOSLASH) == 0)