Module Name: src
Committed By: rillig
Date: Sun Dec 20 19:02:28 UTC 2020
Modified Files:
src/usr.bin/make: var.c
Log Message:
make(1): document that indirect modifiers fall back to SysV modifiers
To generate a diff of this commit:
cvs rdiff -u -r1.751 -r1.752 src/usr.bin/make/var.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/var.c
diff -u src/usr.bin/make/var.c:1.751 src/usr.bin/make/var.c:1.752
--- src/usr.bin/make/var.c:1.751 Sun Dec 20 18:23:24 2020
+++ src/usr.bin/make/var.c Sun Dec 20 19:02:28 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: var.c,v 1.751 2020/12/20 18:23:24 rillig Exp $ */
+/* $NetBSD: var.c,v 1.752 2020/12/20 19:02:28 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1993
@@ -131,7 +131,7 @@
#include "metachar.h"
/* "@(#)var.c 8.3 (Berkeley) 3/19/94" */
-MAKE_RCSID("$NetBSD: var.c,v 1.751 2020/12/20 18:23:24 rillig Exp $");
+MAKE_RCSID("$NetBSD: var.c,v 1.752 2020/12/20 19:02:28 rillig Exp $");
typedef enum VarFlags {
VAR_NONE = 0,
@@ -3420,13 +3420,30 @@ static char *ApplyModifiers(const char *
VarExprFlags *, GNode *, VarEvalFlags, void **);
typedef enum ApplyModifiersIndirectResult {
+ /* The indirect modifiers have been applied successfully. */
AMIR_CONTINUE,
+ /* Fall back to the SysV modifier. */
AMIR_APPLY_MODS,
+ /* Error out. */
AMIR_OUT
} ApplyModifiersIndirectResult;
-/* While expanding a variable expression, expand and apply indirect
- * modifiers such as in ${VAR:${M_indirect}}. */
+/*
+ * While expanding a variable expression, expand and apply indirect modifiers,
+ * such as in ${VAR:${M_indirect}}.
+ *
+ * All indirect modifiers of a group must come from a single variable
+ * expression. ${VAR:${M1}} is valid but ${VAR:${M1}${M2}} is not.
+ *
+ * Multiple groups of indirect modifiers can be chained by separating them
+ * with colons. ${VAR:${M1}:${M2}} contains 2 indirect modifiers.
+ *
+ * If the variable expression is not followed by st->endc or ':', fall
+ * back to trying the SysV modifier, such as in ${VAR:${FROM}=${TO}}.
+ *
+ * The expression ${VAR:${M1}${M2}} is not treated as an indirect
+ * modifier, and it is neither a SysV modifier but a parse error.
+ */
static ApplyModifiersIndirectResult
ApplyModifiersIndirect(ApplyModifiersState *st, const char **pp,
char **inout_val, void **inout_freeIt)
@@ -3437,11 +3454,6 @@ ApplyModifiersIndirect(ApplyModifiersSta
(void)Var_Parse(&p, st->ctxt, st->eflags, &mods);
/* TODO: handle errors */
- /*
- * If we have not parsed up to st->endc or ':', we are not
- * interested. This means the expression ${VAR:${M1}${M2}}
- * is not accepted, but ${VAR:${M1}:${M2}} is.
- */
if (mods.str[0] != '\0' && *p != '\0' && *p != ':' && *p != st->endc) {
if (opts.lint)
Parse_Error(PARSE_FATAL,
@@ -3450,9 +3462,6 @@ ApplyModifiersIndirect(ApplyModifiersSta
(int)(p - *pp), *pp);
FStr_Done(&mods);
- /* XXX: apply_mods doesn't sound like "not interested". */
- /* XXX: Why is the indirect modifier parsed once more by
- * apply_mods? Try *pp = p here. */
return AMIR_APPLY_MODS;
}
@@ -3606,8 +3615,9 @@ ApplyModifiers(
if (amir == AMIR_CONTINUE)
continue;
if (amir == AMIR_OUT)
- goto out;
+ break;
}
+
st.newVal = var_Error; /* default value, in case of errors */
mod = p;
@@ -3618,7 +3628,7 @@ ApplyModifiers(
if (res == AMR_BAD)
goto bad_modifier;
}
-out:
+
*pp = p;
assert(val != NULL); /* Use var_Error or varUndefined instead. */
*exprFlags = st.exprFlags;
