[src/trunk]: src/usr.bin/make make(1): clean up parsing of variable assignments

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a46af9640484
branches:  trunk
changeset: 940155:a46af9640484
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sun Oct 04 20:23:32 2020 +0000

description:
make(1): clean up parsing of variable assignments

diffstat:

 usr.bin/make/nonints.h |   5 ++-
 usr.bin/make/parse.c   |  69 +++++++++++++++++++++++++------------------------
 2 files changed, 38 insertions(+), 36 deletions(-)

diffs (189 lines):

diff -r 225e5177d9a2 -r a46af9640484 usr.bin/make/nonints.h
--- a/usr.bin/make/nonints.h    Sun Oct 04 20:06:48 2020 +0000
+++ b/usr.bin/make/nonints.h    Sun Oct 04 20:23:32 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: nonints.h,v 1.137 2020/10/04 19:36:32 rillig Exp $     */
+/*     $NetBSD: nonints.h,v 1.138 2020/10/04 20:23:32 rillig Exp $     */
 
 /*-
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -130,8 +130,9 @@
 } VarAssignOp;
 
 typedef struct VarAssign {
-    const char *name;          /* unexpanded */
+    const char *nameStart;     /* unexpanded */
     const char *nameEndDraft;  /* before operator adjustment */
+    char *varname;
     const char *eq;            /* the '=' of the assignment operator */
     VarAssignOp op;
     const char *value;         /* unexpanded */
diff -r 225e5177d9a2 -r a46af9640484 usr.bin/make/parse.c
--- a/usr.bin/make/parse.c      Sun Oct 04 20:06:48 2020 +0000
+++ b/usr.bin/make/parse.c      Sun Oct 04 20:23:32 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: parse.c,v 1.356 2020/10/04 19:36:32 rillig Exp $       */
+/*     $NetBSD: parse.c,v 1.357 2020/10/04 20:23:32 rillig Exp $       */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -131,7 +131,7 @@
 #include "pathnames.h"
 
 /*     "@(#)parse.c    8.3 (Berkeley) 3/19/94" */
-MAKE_RCSID("$NetBSD: parse.c,v 1.356 2020/10/04 19:36:32 rillig Exp $");
+MAKE_RCSID("$NetBSD: parse.c,v 1.357 2020/10/04 20:23:32 rillig Exp $");
 
 /* types and constants */
 
@@ -1680,7 +1680,14 @@
     while (*p == ' ' || *p == '\t')
        p++;
 
-    out_var->name = p;
+    out_var->nameStart = p;
+#ifdef CLEANUP
+    out_var->nameEndDraft = NULL;
+    out_var->varname = NULL;
+    out_var->eq = NULL;
+    out_var->op = VAR_NORMAL;
+    out_var->value = NULL;
+#endif
 
     /* Scan for one of the assignment operators outside a variable expansion */
     while ((ch = *p++) != 0) {
@@ -1734,50 +1741,50 @@
     return FALSE;
 }
 
+/* Determine the assignment operator and adjust the end of the variable
+ * name accordingly. */
 static Boolean
-ParseVarassignOp(VarAssign *var,
-                const char **out_op, const char **inout_name,
-                VarAssignOp *out_type, void **inout_name_freeIt, GNode *ctxt)
+ParseVarassignOp(VarAssign *var, const char **out_op, GNode *ctxt)
 {
     const char *op = var->eq;
-    const char *name = *inout_name;
-    void *name_freeIt = *inout_name_freeIt;
+    const char * const nameStart = var->nameStart;
     VarAssignOp type;
 
-    if (op > name && op[-1] == '+') {
+    var->varname = NULL;
+    if (op > nameStart && op[-1] == '+') {
        type = VAR_APPEND;
        op--;
 
-    } else if (op > name && op[-1] == '?') {
+    } else if (op > nameStart && op[-1] == '?') {
        /* If the variable already has a value, we don't do anything. */
        Boolean exists;
        const char *nameEnd;
 
        op--;
        nameEnd = var->nameEndDraft < op ? var->nameEndDraft : op;
-       name = name_freeIt = bmake_strsedup(name, nameEnd);
-       exists = Var_Exists(name, ctxt);
+       var->varname = bmake_strsedup(nameStart, nameEnd);
+       exists = Var_Exists(var->varname, ctxt);
        if (exists) {
-           free(name_freeIt);
+           free(var->varname);
            return FALSE;
        }
        type = VAR_NORMAL;
 
-    } else if (op > name && op[-1] == ':') {
+    } else if (op > nameStart && op[-1] == ':') {
        op--;
        type = VAR_SUBST;
 
-    } else if (op > name && op[-1] == '!') {
+    } else if (op > nameStart && op[-1] == '!') {
        op--;
        type = VAR_SHELL;
 
     } else {
        type = VAR_NORMAL;
 #ifdef SUNSHCMD
-       while (op > name && ch_isspace(op[-1]))
+       while (op > nameStart && ch_isspace(op[-1]))
            op--;
 
-       if (op >= name + 3 && op[-3] == ':' && op[-2] == 's' && op[-1] == 'h') {
+       if (op >= nameStart + 3 && op[-3] == ':' && op[-2] == 's' && op[-1] == 'h') {
            type = VAR_SHELL;
            op -= 3;
        }
@@ -1785,9 +1792,7 @@
     }
 
     *out_op = op;
-    *inout_name = name;
-    *out_type = type;
-    *inout_name_freeIt = name_freeIt;
+    var->op = type;
     return TRUE;
 }
 
@@ -1808,10 +1813,12 @@
 }
 
 static void
-VarAssign_Eval(VarAssignOp const type, const char *const name,
+VarAssign_Eval(VarAssign *var,
          const char *const uvalue, const char **out_avalue, char **out_evalue,
          GNode *ctxt)
 {
+    const char *name = var->varname;
+    const VarAssignOp type = var->op;
     const char *avalue = uvalue;
     char *evalue = NULL;
 
@@ -1914,9 +1921,6 @@
 void
 Parse_DoVar(VarAssign *var, GNode *ctxt)
 {
-    VarAssignOp type;
-    const char *name;
-    void *name_freeIt;
     const char *uvalue;                /* unexpanded value */
     const char *avalue;                /* actual value */
     char *evalue = NULL;       /* expanded value */
@@ -1930,27 +1934,24 @@
      * actual end of the variable name. */
     const char *op;
 
-    name = var->name;
-    name_freeIt = NULL;
-
-    if (!ParseVarassignOp(var, &op, &name, &type, &name_freeIt, ctxt))
+    if (!ParseVarassignOp(var, &op, ctxt))
        return;
 
     uvalue = var->value;
     avalue = uvalue;
 
-    VarCheckSyntax(type, uvalue, ctxt);
+    VarCheckSyntax(var->op, uvalue, ctxt);
 
-    if (name_freeIt == NULL) {
+    if (var->varname == NULL) {
        const char *nameEnd = var->nameEndDraft < op ? var->nameEndDraft : op;
-       name = name_freeIt = bmake_strsedup(name, nameEnd);
+       var->varname = bmake_strsedup(var->nameStart, nameEnd);
     }
 
-    VarAssign_Eval(type, name, uvalue, &avalue, &evalue, ctxt);
-    VarAssignSpecial(name, avalue);
+    VarAssign_Eval(var, uvalue, &avalue, &evalue, ctxt);
+    VarAssignSpecial(var->varname, avalue);
 
     free(evalue);
-    free(name_freeIt);
+    free(var->varname);
 }