date and time created 80/10/08 09:52:24 by kas

SCCS-vsn: usr.bin/mail/vars.c 1.1

diff --git a/usr/src/usr.bin/mail/vars.c b/usr/src/usr.bin/mail/vars.c
new file mode 100644 (file)
index 0000000..82484ff
--- /dev/null
+++ b/usr/src/usr.bin/mail/vars.c
@@ -0,0 +1,158 @@
+#
+
+#include "rcv.h"
+
+/*
+ * Mail -- a mail program
+ *
+ * Variable handling stuff.
+ */
+
+static char *SccsId = "@(#)vars.c      1.1 %G%";
+
+/*
+ * Assign a value to a variable.
+ */
+
+assign(name, value)
+       char name[], value[];
+{
+       register struct var *vp;
+       register int h;
+
+       h = hash(name);
+       vp = lookup(name);
+       if (vp == NOVAR) {
+               vp = (struct var *) calloc(sizeof *vp, 1);
+               vp->v_name = vcopy(name);
+               vp->v_link = variables[h];
+               variables[h] = vp;
+       }
+       else
+               vfree(vp->v_value);
+       vp->v_value = vcopy(value);
+}
+
+/*
+ * Free up a variable string.  We do not bother to allocate
+ * strings whose value is "" since they are expected to be frequent.
+ * Thus, we cannot free same!
+ */
+
+vfree(cp)
+       register char *cp;
+{
+       if (!equal(cp, ""))
+               cfree(cp);
+}
+
+/*
+ * Copy a variable value into permanent (ie, not collected after each
+ * command) space.  Do not bother to alloc space for ""
+ */
+
+char *
+vcopy(str)
+       char str[];
+{
+       register char *top, *cp, *cp2;
+
+       if (equal(str, ""))
+               return("");
+       top = calloc(strlen(str)+1, 1);
+       cp = top;
+       cp2 = str;
+       while (*cp++ = *cp2++)
+               ;
+       return(top);
+}
+
+/*
+ * Get the value of a variable and return it.
+ * Look in the environment if its not available locally.
+ */
+
+char *
+value(name)
+       char name[];
+{
+       register struct var *vp;
+
+       if ((vp = lookup(name)) == NOVAR)
+               return(getenv(name));
+       return(vp->v_value);
+}
+
+/*
+ * Locate a variable and return its variable
+ * node.
+ */
+
+struct var *
+lookup(name)
+       char name[];
+{
+       register struct var *vp;
+       register int h;
+
+       h = hash(name);
+       for (vp = variables[h]; vp != NOVAR; vp = vp->v_link)
+               if (equal(vp->v_name, name))
+                       return(vp);
+       return(NOVAR);
+}
+
+/*
+ * Locate a group name and return it.
+ */
+
+struct grouphead *
+findgroup(name)
+       char name[];
+{
+       register struct grouphead *gh;
+       register int h;
+
+       h = hash(name);
+       for (gh = groups[h]; gh != NOGRP; gh = gh->g_link)
+               if (equal(gh->g_name, name))
+                       return(gh);
+       return(NOGRP);
+}
+
+/*
+ * Print a group out on stdout
+ */
+
+printgroup(name)
+       char name[];
+{
+       register struct grouphead *gh;
+       register struct group *gp;
+
+       if ((gh = findgroup(name)) == NOGRP) {
+               printf("\"%s\": not a group\n", name);
+               return;
+       }
+       printf("%s\t", gh->g_name);
+       for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
+               printf(" %s", gp->ge_name);
+       printf("\n");
+}
+
+/*
+ * Hash the passed string and return an index into
+ * the variable or group hash table.
+ */
+
+hash(name)
+       char name[];
+{
+       register int h;
+       register char *cp;
+
+       for (cp = name, h = 0; *cp; h = (h << 2) + *cp++)
+               ;
+       h &= ~0100000;
+       return(h % HSHSIZE);
+}