rev_dep expressions can get rather unwieldy, especially if a symbol is
selected by more than a handful of other symbols. Ie, it's possible to
have near endless expressions like:
A && B && !C || D || F && (G || H) || [...]
Chop these expressions into actually readable chunks:
- A && B && !C
- D
- F && (G || H)
- [...]
Ie, transform the top level "||" tokens into newlines and prepend each
line with a minus. This makes the "Selected by:" blurb much easier to
read.
Cc: Paul Bolle <pebolle@xxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
---
Today I found myself wondering why a certain Kconfig was selected.
Currently menuconfig's help is of no use in complicated cases. Please
look at the help of USB or CRYPTO to see what I mean.
This is a _hack_ to show what might be a better way to do this. It
parses a stringified version of the reverse dependency, and not the
actual reverse dependecy expression. But that was easier to cobble
together.
One cool improvement would be to change to minus in front of the
subexpressions to Y or M for those that actually set the symbol. Anyhow,
other suggestions and feedback is welcome.
Signed-off-by: Petr Vorel <petr.vorel@xxxxxxxxx>
---
Changes v1->v2:
Rewrote Paul Bolle's original implementation: removed use of
expr_gstr_print()'s output from rev_dep_gstr_print(). I admit that
adding revdep variable and wrapper function isn't a nice solution, but
it works directly with struct expr :-).
---
scripts/kconfig/expr.c | 36 ++++++++++++++++++++++++++++++++----
scripts/kconfig/expr.h | 1 +
scripts/kconfig/menu.c | 4 ++--
3 files changed, 35 insertions(+), 6 deletions(-)
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
index 667d1aa..af0e840 100644
--- a/scripts/kconfig/expr.c
+++ b/scripts/kconfig/expr.c
@@ -1070,7 +1070,7 @@ struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2)
return expr_get_leftmost_symbol(ret);
}
-void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken)
+static void expr_print_impl(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken, bool revdep)
{
if (!e) {
fn(data, NULL, "y");
@@ -1125,9 +1125,12 @@ void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *
fn(data, e->right.sym, e->right.sym->name);
break;
case E_OR:
- expr_print(e->left.expr, fn, data, E_OR);
- fn(data, NULL, " || ");
- expr_print(e->right.expr, fn, data, E_OR);
+ expr_print_impl(e->left.expr, fn, data, E_OR, revdep);
+ if (revdep)
+ fn(data, NULL, "\n - ");
+ else
+ fn(data, NULL, " || ");
+ expr_print_impl(e->right.expr, fn, data, E_OR, revdep);
break;
case E_AND:
expr_print(e->left.expr, fn, data, E_AND);
@@ -1160,6 +1163,11 @@ void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *
fn(data, NULL, ")");
}
+void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken)
+{
+ expr_print_impl(e, fn, data, prevtoken, false);
+}
+
static void expr_print_file_helper(void *data, struct symbol *sym, const char *str)
{
xfwrite(str, strlen(str), 1, data);
@@ -1204,3 +1212,23 @@ void expr_gstr_print(struct expr *e, struct gstr *gs)
{
expr_print(e, expr_print_gstr_helper, gs, E_NONE);
}
+
+/*
+ * rev_dep expressions can get rather unwieldy, especially if a symbol is
+ * selected by more than a handful of other symbols. Ie, it's possible to
+ * have near endless expressions like:
+ * A && B && !C || D || F && (G || H) || [...]
+ *
+ * Chop these expressions into actually readable chunks:
+ * - A && B && !C
+ * - D
+ * - F && (G || H)
+ * - [...]
+ *
+ * Ie, transform the top level "||" tokens into newlines and prepend each line
+ * with a minus. This makes the "Selected by:" blurb much easier to read.
+ */
+void rev_dep_gstr_print(struct expr *e, struct gstr *gs)
+{
+ expr_print_impl(e, expr_print_gstr_helper, gs, E_NONE, true);
+}
diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 973b6f7..f3bf88d 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -220,6 +220,7 @@ struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2);
void expr_fprint(struct expr *e, FILE *out);
struct gstr; /* forward */
void expr_gstr_print(struct expr *e, struct gstr *gs);
+void rev_dep_gstr_print(struct expr *e, struct gstr *gs);
static inline int expr_is_yes(struct expr *e)
{
diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index b05cc3d..b6b383e 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -661,8 +661,8 @@ static void get_symbol_str(struct gstr *r, struct symbol *sym,
str_append(r, "\n");
if (sym->rev_dep.expr) {
str_append(r, _(" Selected by: "));
- expr_gstr_print(sym->rev_dep.expr, r);
- str_append(r, "\n");
+ str_append(r, "\n - ");
+ rev_dep_gstr_print(sym->rev_dep.expr, r);
}
str_append(r, "\n\n");
}
--
2.5.3
--
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