1 /* remcap.c 4.1 81/05/09 */ 2 /* Copyright (c) 1979 Regents of the University of California */ 3 #define BUFSIZ 512 4 5 #include <ctype.h> 6 /* 7 * remcap - routines for dealing with the remote host description 8 * data base 9 * 10 * BUG: Should use a "last" pointer in tbuf, so that searching 11 * for capabilities alphabetically would not be a n**2/2 12 * process when large numbers of capabilities are given. 13 * 14 * Essentially all the work here is scanning and decoding escapes 15 * in string capabilities.*/ 16 17 static char *rbuf; 18 char *rskip(); 19 char *rgetstr(); 20 char *rdecode(); 21 char *getenv(); 22 char *RM; /* remote file */ 23 24 /* 25 * Get an entry for host name in buffer bp, 26 * from the remcap file. Parse is very rudimentary; 27 * we just notice escaped newlines. 28 */ 29 rgetent(bp, name) 30 char *bp, *name; 31 { 32 register char *cp; 33 register int c; 34 register int i = 0, cnt = 0; 35 char ibuf[BUFSIZ]; 36 int tf; 37 38 rbuf = bp; 39 if ((RM = getenv("REMOTE")) == (char *)0) 40 RM = "/etc/remote"; 41 if ((tf = open(RM, 0)) < 0) 42 return (-1); 43 for (;;) { 44 cp = bp; 45 for (;;) { 46 if (i == cnt) { 47 cnt = read(tf, ibuf, BUFSIZ); 48 if (cnt <= 0) { 49 close(tf); 50 return (0); 51 } 52 i = 0; 53 } 54 c = ibuf[i++]; 55 if (c == '\n') { 56 if (cp > bp && cp[-1] == '\\'){ 57 cp--; 58 continue; 59 } 60 break; 61 } 62 *cp++ = c; 63 } 64 *cp = 0; 65 66 /* 67 * The real work for the match. 68 */ 69 if (rnamatch(name)) { 70 close(tf); 71 return (1); 72 } 73 } 74 } 75 76 /* 77 * Rnamatch deals with name matching. The first field of the remcap 78 * entry is a sequence of names separated by |'s, so we compare 79 * against each such name. The normal : terminator after the last 80 * name (before the first field) stops us. 81 */ 82 rnamatch(np) 83 char *np; 84 { 85 register char *Np, *Bp; 86 87 Bp = rbuf; 88 for (;;) { 89 for (Np = np; *Np && *Bp == *Np; Bp++, Np++) 90 continue; 91 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0)) 92 return (1); 93 while (*Bp && *Bp != ':' && *Bp != '|') 94 Bp++; 95 if (*Bp == 0 || *Bp == ':') 96 return (0); 97 Bp++; 98 } 99 } 100 101 /* 102 * Skip to the next field. Notice that this is very dumb, not 103 * knowing about \: escapes or any such. If necessary, :'s can be put 104 * into the printcap file in octal. 105 */ 106 static char * 107 rskip(bp) 108 register char *bp; 109 { 110 111 while (*bp && *bp != ':') 112 bp++; 113 if (*bp == ':') 114 bp++; 115 return (bp); 116 } 117 118 /* 119 * Return the (numeric) option id. 120 * Numeric options look like 121 * li#80 122 * i.e. the option string is separated from the numeric value by 123 * a # character. If the option is not found we return -1. 124 * Note that we handle octal numbers beginning with 0. 125 */ 126 rgetnum(id) 127 char *id; 128 { 129 register int i, base; 130 register char *bp = rbuf; 131 132 for (;;) { 133 bp = rskip(bp); 134 if (*bp == 0) 135 return (-1); 136 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1]) 137 continue; 138 if (*bp != '#') 139 continue; 140 bp++; 141 base = 10; 142 if (*bp == '0') 143 base = 8; 144 i = 0; 145 while (isdigit(*bp)) 146 i *= base, i += *bp++ - '0'; 147 return (i); 148 } 149 } 150 151 /* 152 * Handle a flag option. 153 * Flag options are given "naked", i.e. followed by a : or the end 154 * of the buffer. Return 1 if we find the option, or 0 if it is 155 * not given. 156 */ 157 rgetflag(id) 158 char *id; 159 { 160 register char *bp = rbuf; 161 162 for (;;) { 163 bp = rskip(bp); 164 if (!*bp) 165 return (0); 166 if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1] && (!*bp || *bp == ':')) 167 return (1); 168 } 169 } 170 171 /* 172 * Get a string valued option. 173 * These are given as 174 * cl=^Z 175 * Much decoding is done on the strings, and the strings are 176 * placed in area, which is a ref parameter which is updated. 177 * No checking on area overflow. 178 */ 179 char * 180 rgetstr(id, area) 181 char *id, **area; 182 { 183 register char *bp = rbuf; 184 185 for (;;) { 186 bp = rskip(bp); 187 if (!*bp) 188 return (0); 189 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1]) 190 continue; 191 if (*bp != '=') 192 continue; 193 bp++; 194 return (rdecode(bp, area)); 195 } 196 } 197 198 /* 199 * Tdecode does the grung work to decode the 200 * string capability escapes. 201 */ 202 char * 203 rdecode(str, area) 204 register char *str; 205 char **area; 206 { 207 register char *cp; 208 register int c; 209 register char *dp; 210 int i; 211 212 cp = *area; 213 while ((c = *str++) && c != ':') { 214 switch (c) { 215 216 case '^': 217 c = *str++ & 037; 218 break; 219 220 case '\\': 221 dp = "E\033^^\\\\::n\nr\rt\tb\bf\f"; 222 c = *str++; 223 nextc: 224 if (*dp++ == c) { 225 c = *dp++; 226 break; 227 } 228 dp++; 229 if (*dp) 230 goto nextc; 231 if (isdigit(c)) { 232 c -= '0', i = 2; 233 do 234 c <<= 3, c |= *str++ - '0'; 235 while (--i && isdigit(*str)); 236 } 237 break; 238 } 239 *cp++ = c; 240 } 241 *cp++ = 0; 242 str = *area; 243 *area = cp; 244 return (str); 245 } 246