2 * vis functions - visually encode characters
3 * Originally from OpenBSD
7 * Copyright (c) 1989, 1993
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39 #include <sys/types.h>
43 * to select alternate encoding format
45 #define VIS_OCTAL 0x01 /* use octal \ddd format */
46 #define VIS_CSTYLE 0x02 /* use \[nrft0..] where appropriate */
48 * to alter set of characters encoded (default is to encode all
49 * non-graphic except space, tab, and newline).
51 #define VIS_SP 0x04 /* also encode space */
52 #define VIS_TAB 0x08 /* also encode tab */
53 #define VIS_NL 0x10 /* also encode newline */
54 #define VIS_WHITE (VIS_SP | VIS_TAB | VIS_NL)
55 #define VIS_SAFE 0x20 /* only encode "unsafe" characters */
57 #define VIS_NOSLASH 0x40 /* inhibit printing '\' */
62 #define UNVIS_VALID 1 /* character valid */
63 #define UNVIS_VALIDPUSH 2 /* character valid, push back passed char */
64 #define UNVIS_NOCHAR 3 /* valid sequence, no character produced */
65 #define UNVIS_SYNBAD -1 /* unrecognized escape sequence */
66 #define UNVIS_ERROR -2 /* decoder in unknown state (unrecoverable) */
71 #define UNVIS_END 1 /* no more characters */
73 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
74 #define isvisible(c) (((u_int)(c) <= UCHAR_MAX && isascii((u_char)(c)) && \
75 isgraph((u_char)(c))) || \
76 ((flag & VIS_SP) == 0 && (c) == ' ') || \
77 ((flag & VIS_TAB) == 0 && (c) == '\t') || \
78 ((flag & VIS_NL) == 0 && (c) == '\n') || \
79 ((flag & VIS_SAFE) && \
80 ((c) == '\b' || (c) == '\007' || (c) == '\r')))
83 * decode driven by state machine
85 #define S_GROUND 0 /* haven't seen escape char */
86 #define S_START 1 /* start decoding special sequence */
87 #define S_META 2 /* metachar started (M) */
88 #define S_META1 3 /* metachar more, regular char (-) */
89 #define S_CTRL 4 /* control char started (^) */
90 #define S_OCTAL2 5 /* octal digit 2 */
91 #define S_OCTAL3 6 /* octal digit 3 */
93 char *vis(char *, int, int, int);
94 int strvis(char *, const char *, int);
95 int strnvis(char *, const char *, size_t, int);
96 int strvisx(char *, const char *, size_t, int);
97 int strunvis(char *, const char *);
98 int unvis(char *, char, int *, int);