BSD 2 development

Work on file src/termlib/termcap.c

Synthesized-from: 2bsd

diff --git a/src/termlib/termcap.c b/src/termlib/termcap.c
new file mode 100644 (file)
index 0000000..741e277
--- /dev/null
+++ b/src/termlib/termcap.c
@@ -0,0 +1,247 @@
+/* Copyright (c) 1979 Regents of the University of California */
+#define        BUFSIZ  512
+
+#include <ctype.h>
+/*
+ * termcap - routines for dealing with the terminal capability data base
+ *
+ * BUG:                Should use a "last" pointer in tbuf, so that searching
+ *             for capabilities alphabetically would not be a n**2/2
+ *             process when large numbers of capabilities are given.
+ *
+ * Essentially all the work here is scanning and decoding escapes
+ * in string capabilities.  We don't use stdio because the editor
+ * doesn't, and because living w/o it is not hard.
+ */
+
+static char *tbuf;
+char   *tskip();
+char   *tgetstr();
+char   *tdecode();
+
+/*
+ * Get an entry for terminal name in buffer bp,
+ * from the termcap file.  Parse is very rudimentary;
+ * we just notice escaped newlines.
+ */
+tgetent(bp, name)
+       char *bp, *name;
+{
+       register char *cp;
+       register int c;
+       register int i = 0, cnt = 0;
+       char ibuf[BUFSIZ];
+       int tf;
+
+       tbuf = bp;
+#ifndef V6
+       cp = getenv("TERMCAP");
+       tf = open(cp ? cp : "/etc/termcap", 0);
+#else
+       tf = open("/etc/termcap", 0);
+#endif
+       if (tf < 0)
+               return (-1);
+       for (;;) {
+               cp = bp;
+               for (;;) {
+                       if (i == cnt) {
+                               cnt = read(tf, ibuf, BUFSIZ);
+                               if (cnt <= 0) {
+                                       close(tf);
+                                       return (0);
+                               }
+                               i = 0;
+                       }
+                       c = ibuf[i++];
+                       if (c == '\n') {
+                               if (cp > bp && cp[-1] == '\\'){
+                                       cp--;
+                                       continue;
+                               }
+                               break;
+                       }
+                       *cp++ = c;
+               }
+               *cp = 0;
+
+               /*
+                * The real work for the match.
+                */
+               if (tnamatch(name)) {
+                       close(tf);
+                       return (1);
+               }
+       }
+}
+
+/*
+ * Tnamatch deals with name matching.  The first field of the termcap
+ * entry is a sequence of names separated by |'s, so we compare
+ * against each such name.  The normal : terminator after the last
+ * name (before the first field) stops us.
+ */
+tnamatch(np)
+       char *np;
+{
+       register char *Np, *Bp;
+
+       Bp = tbuf;
+       for (;;) {
+               for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
+                       continue;
+               if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
+                       return (1);
+               while (*Bp && *Bp != ':' && *Bp != '|')
+                       Bp++;
+               if (*Bp == 0 || *Bp == ':')
+                       return (0);
+               Bp++;
+       }
+}
+
+/*
+ * Skip to the next field.  Notice that this is very dumb, not
+ * knowing about \: escapes or any such.  If necessary, :'s can be put
+ * into the termcap file in octal.
+ */
+static char *
+tskip(bp)
+       register char *bp;
+{
+
+       while (*bp && *bp != ':')
+               bp++;
+       if (*bp == ':')
+               bp++;
+       return (bp);
+}
+
+/*
+ * Return the (numeric) option id.
+ * Numeric options look like
+ *     li#80
+ * i.e. the option string is separated from the numeric value by
+ * a # character.  If the option is not found we return -1.
+ * Note that we handle octal numbers beginning with 0.
+ */
+tgetnum(id)
+       char *id;
+{
+       register int i, base;
+       register char *bp = tbuf;
+
+       for (;;) {
+               bp = tskip(bp);
+               if (*bp == 0)
+                       return (-1);
+               if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
+                       continue;
+               if (*bp != '#')
+                       continue;
+               bp++;
+               base = 10;
+               if (*bp == '0')
+                       base = 8;
+               i = 0;
+               while (isdigit(*bp))
+                       i *= base, i += *bp++ - '0';
+               return (i);
+       }
+}
+
+/*
+ * Handle a flag option.
+ * Flag options are given "naked", i.e. followed by a : or the end
+ * of the buffer.  Return 1 if we find the option, or 0 if it is
+ * not given.
+ */
+tgetflag(id)
+       char *id;
+{
+       register char *bp = tbuf;
+
+       for (;;) {
+               bp = tskip(bp);
+               if (!*bp)
+                       return (0);
+               if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1] && (!*bp || *bp == ':'))
+                       return (1);
+       }
+}
+
+/*
+ * Get a string valued option.
+ * These are given as
+ *     cl=^Z
+ * Much decoding is done on the strings, and the strings are
+ * placed in area, which is a ref parameter which is updated.
+ * No checking on area overflow.
+ */
+char *
+tgetstr(id, area)
+       char *id, **area;
+{
+       register char *bp = tbuf;
+
+       for (;;) {
+               bp = tskip(bp);
+               if (!*bp)
+                       return (0);
+               if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
+                       continue;
+               if (*bp != '=')
+                       continue;
+               bp++;
+               return (tdecode(bp, area));
+       }
+}
+
+/*
+ * Tdecode does the grung work to decode the
+ * string capability escapes.
+ */
+static char *
+tdecode(str, area)
+       register char *str;
+       char **area;
+{
+       register char *cp;
+       register int c;
+       register char *dp;
+       int i;
+
+       cp = *area;
+       while ((c = *str++) && c != ':') {
+               switch (c) {
+
+               case '^':
+                       c = *str++ & 037;
+                       break;
+
+               case '\\':
+                       dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
+                       c = *str++;
+nextc:
+                       if (*dp++ == c) {
+                               c = *dp++;
+                               break;
+                       }
+                       dp++;
+                       if (*dp)
+                               goto nextc;
+                       if (isdigit(c)) {
+                               c -= '0', i = 2;
+                               do
+                                       c <<= 3, c |= *str++ - '0';
+                               while (--i && isdigit(*str));
+                       }
+                       break;
+               }
+               *cp++ = c;
+       }
+       *cp++ = 0;
+       str = *area;
+       *area = cp;
+       return (str);
+}