From f954a53a9a7dced3fb4c80b1e8dd267981ae025d Mon Sep 17 00:00:00 2001 From: cvs2svn Date: Mon, 19 Oct 1998 21:47:13 +0000 Subject: This commit was manufactured by cvs2git to create branch 'OPENBSD_2_4'. --- src/lib/libc/stdlib/tfind.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 src/lib/libc/stdlib/tfind.c (limited to 'src/lib/libc/stdlib/tfind.c') diff --git a/src/lib/libc/stdlib/tfind.c b/src/lib/libc/stdlib/tfind.c new file mode 100644 index 0000000000..9e5bd4b0f2 --- /dev/null +++ b/src/lib/libc/stdlib/tfind.c @@ -0,0 +1,41 @@ +/* + * Tree search generalized from Knuth (6.2.2) Algorithm T just like + * the AT&T man page says. + * + * The node_t structure is for internal use only, lint doesn't grok it. + * + * Written by reading the System V Interface Definition, not the code. + * + * Totally public domain. + */ +/*LINTLIBRARY*/ +#include + +typedef struct node_t +{ + char *key; + struct node_t *llink, *rlink; +} node; + +/* find a node, or return 0 */ +void * +tfind(vkey, vrootp, compar) + const void *vkey; /* key to be found */ + void *const *vrootp; /* address of the tree root */ + int (*compar) __P((const void *, const void *)); +{ + char *key = (char *)vkey; + node **rootp = (node **)vrootp; + + if (rootp == (struct node_t **)0) + return ((struct node_t *)0); + while (*rootp != (struct node_t *)0) { /* T1: */ + int r; + if ((r = (*compar)(key, (*rootp)->key)) == 0) /* T2: */ + return (*rootp); /* key found */ + rootp = (r < 0) ? + &(*rootp)->llink : /* T3: follow left branch */ + &(*rootp)->rlink; /* T4: follow right branch */ + } + return (node *)0; +} -- cgit v1.2.3-55-g6feb