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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /usr.bin/indent/parse.c
initial import of NetBSD tree
Diffstat (limited to 'usr.bin/indent/parse.c')
-rw-r--r--usr.bin/indent/parse.c325
1 files changed, 325 insertions, 0 deletions
diff --git a/usr.bin/indent/parse.c b/usr.bin/indent/parse.c
new file mode 100644
index 00000000000..e5b8453a92e
--- /dev/null
+++ b/usr.bin/indent/parse.c
@@ -0,0 +1,325 @@
+/*
+ * Copyright (c) 1985 Sun Microsystems, Inc.
+ * Copyright (c) 1980 The Regents of the University of California.
+ * Copyright (c) 1976 Board of Trustees of the University of Illinois.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+/*static char sccsid[] = "from: @(#)parse.c 5.12 (Berkeley) 2/26/91";*/
+static char rcsid[] = "$Id: parse.c,v 1.1 1995/10/18 08:45:25 deraadt Exp $";
+#endif /* not lint */
+
+#include <stdio.h>
+#include "indent_globs.h"
+#include "indent_codes.h"
+
+parse(tk)
+ int tk; /* the code for the construct scanned */
+{
+ int i;
+
+#ifdef debug
+ printf("%2d - %s\n", tk, token);
+#endif
+
+ while (ps.p_stack[ps.tos] == ifhead && tk != elselit) {
+ /* true if we have an if without an else */
+ ps.p_stack[ps.tos] = stmt; /* apply the if(..) stmt ::= stmt
+ * reduction */
+ reduce(); /* see if this allows any reduction */
+ }
+
+
+ switch (tk) { /* go on and figure out what to do with the
+ * input */
+
+ case decl: /* scanned a declaration word */
+ ps.search_brace = btype_2;
+ /* indicate that following brace should be on same line */
+ if (ps.p_stack[ps.tos] != decl) { /* only put one declaration
+ * onto stack */
+ break_comma = true; /* while in declaration, newline should be
+ * forced after comma */
+ ps.p_stack[++ps.tos] = decl;
+ ps.il[ps.tos] = ps.i_l_follow;
+
+ if (ps.ljust_decl) {/* only do if we want left justified
+ * declarations */
+ ps.ind_level = 0;
+ for (i = ps.tos - 1; i > 0; --i)
+ if (ps.p_stack[i] == decl)
+ ++ps.ind_level; /* indentation is number of
+ * declaration levels deep we are */
+ ps.i_l_follow = ps.ind_level;
+ }
+ }
+ break;
+
+ case ifstmt: /* scanned if (...) */
+ if (ps.p_stack[ps.tos] == elsehead && ps.else_if) /* "else if ..." */
+ ps.i_l_follow = ps.il[ps.tos];
+ case dolit: /* 'do' */
+ case forstmt: /* for (...) */
+ ps.p_stack[++ps.tos] = tk;
+ ps.il[ps.tos] = ps.ind_level = ps.i_l_follow;
+ ++ps.i_l_follow; /* subsequent statements should be indented 1 */
+ ps.search_brace = btype_2;
+ break;
+
+ case lbrace: /* scanned { */
+ break_comma = false; /* don't break comma in an initial list */
+ if (ps.p_stack[ps.tos] == stmt || ps.p_stack[ps.tos] == decl
+ || ps.p_stack[ps.tos] == stmtl)
+ ++ps.i_l_follow; /* it is a random, isolated stmt group or a
+ * declaration */
+ else {
+ if (s_code == e_code) {
+ /*
+ * only do this if there is nothing on the line
+ */
+ --ps.ind_level;
+ /*
+ * it is a group as part of a while, for, etc.
+ */
+ if (ps.p_stack[ps.tos] == swstmt && ps.case_indent >= 1)
+ --ps.ind_level;
+ /*
+ * for a switch, brace should be two levels out from the code
+ */
+ }
+ }
+
+ ps.p_stack[++ps.tos] = lbrace;
+ ps.il[ps.tos] = ps.ind_level;
+ ps.p_stack[++ps.tos] = stmt;
+ /* allow null stmt between braces */
+ ps.il[ps.tos] = ps.i_l_follow;
+ break;
+
+ case whilestmt: /* scanned while (...) */
+ if (ps.p_stack[ps.tos] == dohead) {
+ /* it is matched with do stmt */
+ ps.ind_level = ps.i_l_follow = ps.il[ps.tos];
+ ps.p_stack[++ps.tos] = whilestmt;
+ ps.il[ps.tos] = ps.ind_level = ps.i_l_follow;
+ }
+ else { /* it is a while loop */
+ ps.p_stack[++ps.tos] = whilestmt;
+ ps.il[ps.tos] = ps.i_l_follow;
+ ++ps.i_l_follow;
+ ps.search_brace = btype_2;
+ }
+
+ break;
+
+ case elselit: /* scanned an else */
+
+ if (ps.p_stack[ps.tos] != ifhead)
+ diag(1, "Unmatched 'else'");
+ else {
+ ps.ind_level = ps.il[ps.tos]; /* indentation for else should
+ * be same as for if */
+ ps.i_l_follow = ps.ind_level + 1; /* everything following should
+ * be in 1 level */
+ ps.p_stack[ps.tos] = elsehead;
+ /* remember if with else */
+ ps.search_brace = btype_2 | ps.else_if;
+ }
+ break;
+
+ case rbrace: /* scanned a } */
+ /* stack should have <lbrace> <stmt> or <lbrace> <stmtl> */
+ if (ps.p_stack[ps.tos - 1] == lbrace) {
+ ps.ind_level = ps.i_l_follow = ps.il[--ps.tos];
+ ps.p_stack[ps.tos] = stmt;
+ }
+ else
+ diag(1, "Stmt nesting error.");
+ break;
+
+ case swstmt: /* had switch (...) */
+ ps.p_stack[++ps.tos] = swstmt;
+ ps.cstk[ps.tos] = case_ind;
+ /* save current case indent level */
+ ps.il[ps.tos] = ps.i_l_follow;
+ case_ind = ps.i_l_follow + ps.case_indent; /* cases should be one
+ * level down from
+ * switch */
+ ps.i_l_follow += ps.case_indent + 1; /* statements should be two
+ * levels in */
+ ps.search_brace = btype_2;
+ break;
+
+ case semicolon: /* this indicates a simple stmt */
+ break_comma = false; /* turn off flag to break after commas in a
+ * declaration */
+ ps.p_stack[++ps.tos] = stmt;
+ ps.il[ps.tos] = ps.ind_level;
+ break;
+
+ default: /* this is an error */
+ diag(1, "Unknown code to parser");
+ return;
+
+
+ } /* end of switch */
+
+ reduce(); /* see if any reduction can be done */
+
+#ifdef debug
+ for (i = 1; i <= ps.tos; ++i)
+ printf("(%d %d)", ps.p_stack[i], ps.il[i]);
+ printf("\n");
+#endif
+
+ return;
+}
+
+/*
+ * NAME: reduce
+ *
+ * FUNCTION: Implements the reduce part of the parsing algorithm
+ *
+ * ALGORITHM: The following reductions are done. Reductions are repeated
+ * until no more are possible.
+ *
+ * Old TOS New TOS
+ * <stmt> <stmt> <stmtl>
+ * <stmtl> <stmt> <stmtl>
+ * do <stmt> "dostmt"
+ * if <stmt> "ifstmt"
+ * switch <stmt> <stmt>
+ * decl <stmt> <stmt>
+ * "ifelse" <stmt> <stmt>
+ * for <stmt> <stmt>
+ * while <stmt> <stmt>
+ * "dostmt" while <stmt>
+ *
+ * On each reduction, ps.i_l_follow (the indentation for the following line)
+ * is set to the indentation level associated with the old TOS.
+ *
+ * PARAMETERS: None
+ *
+ * RETURNS: Nothing
+ *
+ * GLOBALS: ps.cstk ps.i_l_follow = ps.il ps.p_stack = ps.tos =
+ *
+ * CALLS: None
+ *
+ * CALLED BY: parse
+ *
+ * HISTORY: initial coding November 1976 D A Willcox of CAC
+ *
+ */
+/*----------------------------------------------*\
+| REDUCTION PHASE |
+\*----------------------------------------------*/
+reduce()
+{
+
+ register int i;
+
+ for (;;) { /* keep looping until there is nothing left to
+ * reduce */
+
+ switch (ps.p_stack[ps.tos]) {
+
+ case stmt:
+ switch (ps.p_stack[ps.tos - 1]) {
+
+ case stmt:
+ case stmtl:
+ /* stmtl stmt or stmt stmt */
+ ps.p_stack[--ps.tos] = stmtl;
+ break;
+
+ case dolit: /* <do> <stmt> */
+ ps.p_stack[--ps.tos] = dohead;
+ ps.i_l_follow = ps.il[ps.tos];
+ break;
+
+ case ifstmt:
+ /* <if> <stmt> */
+ ps.p_stack[--ps.tos] = ifhead;
+ for (i = ps.tos - 1;
+ (
+ ps.p_stack[i] != stmt
+ &&
+ ps.p_stack[i] != stmtl
+ &&
+ ps.p_stack[i] != lbrace
+ );
+ --i);
+ ps.i_l_follow = ps.il[i];
+ /*
+ * for the time being, we will assume that there is no else on
+ * this if, and set the indentation level accordingly. If an
+ * else is scanned, it will be fixed up later
+ */
+ break;
+
+ case swstmt:
+ /* <switch> <stmt> */
+ case_ind = ps.cstk[ps.tos - 1];
+
+ case decl: /* finish of a declaration */
+ case elsehead:
+ /* <<if> <stmt> else> <stmt> */
+ case forstmt:
+ /* <for> <stmt> */
+ case whilestmt:
+ /* <while> <stmt> */
+ ps.p_stack[--ps.tos] = stmt;
+ ps.i_l_follow = ps.il[ps.tos];
+ break;
+
+ default: /* <anything else> <stmt> */
+ return;
+
+ } /* end of section for <stmt> on top of stack */
+ break;
+
+ case whilestmt: /* while (...) on top */
+ if (ps.p_stack[ps.tos - 1] == dohead) {
+ /* it is termination of a do while */
+ ps.p_stack[--ps.tos] = stmt;
+ break;
+ }
+ else
+ return;
+
+ default: /* anything else on top */
+ return;
+
+ }
+ }
+}