print: improve indented printing api

- make sure all commit errors go to stderr
- make it a bit more api like

src/apk_print.h

@@ -63,10 +63,14 @@ struct apk_progress {
 void apk_print_progress(struct apk_progress *p, size_t done, size_t total);
 
 struct apk_indent {
-	struct apk_out *out;
-	int x, indent;
+	FILE *f;
+	unsigned int x, indent, width;
 };
 
+void apk_print_indented_init(struct apk_indent *i, struct apk_out *out, int err);
+void apk_print_indented_line(struct apk_indent *i, const char *fmt, ...);
+void apk_print_indented_group(struct apk_indent *i, int indent, const char *fmt, ...);
+void apk_print_indented_end(struct apk_indent *i);
 int  apk_print_indented(struct apk_indent *i, apk_blob_t blob);
 void apk_print_indented_words(struct apk_indent *i, const char *text);
 void apk_print_indented_fmt(struct apk_indent *i, const char *fmt, ...)

src/app_del.c

@@ -68,14 +68,10 @@ static void print_not_deleted_pkg(struct apk_package *pkg0, struct apk_dependenc
 		apk_msg(out, "World updated, but the following packages are not removed due to:");
 		ctx->header = 1;
 	}
-	if (!ctx->indent.indent) {
-		ctx->indent.x = printf("  %s:", ctx->name->name);
-		ctx->indent.indent = ctx->indent.x + 1;
-	}
-
-	if (name_in_world(pkg0->name)) {
+	if (!ctx->indent.indent)
+		apk_print_indented_group(&ctx->indent, 0, "  %s:", ctx->name->name);
+	if (name_in_world(pkg0->name))
 		apk_print_indented(&ctx->indent, APK_BLOB_STR(pkg0->name->name));
-	}
 	foreach_array_item(d, pkg0->provides) {
 		if (!name_in_world(d->name)) continue;
 		apk_print_indented(&ctx->indent, APK_BLOB_STR(d->name->name));
@@ -98,14 +94,13 @@ static void print_not_deleted_name(struct apk_database *db, const char *match,
 	struct not_deleted_ctx *ctx = (struct not_deleted_ctx *) pctx;
 	struct apk_provider *p;
 
-	ctx->indent = (struct apk_indent) { .out = out };
 	ctx->name = name;
 	ctx->matches = apk_foreach_genid() | APK_FOREACH_MARKED | APK_DEP_SATISFIES;
+	apk_print_indented_init(&ctx->indent, out, 0);
 	foreach_array_item(p, name->providers)
 		if (p->pkg->marked)
 			print_not_deleted_pkg(p->pkg, NULL, NULL, ctx);
-	if (ctx->indent.indent)
-		printf("\n");
+	apk_print_indented_end(&ctx->indent);
 }
 
 static void delete_pkg(struct apk_package *pkg0, struct apk_dependency *dep0,

src/commit.c

@@ -133,14 +133,13 @@ static int dump_packages(struct apk_out *out, struct apk_changeset *changeset,
 {
 	struct apk_change *change;
 	struct apk_name *name;
-	struct apk_indent indent = { .out = out, .indent = 2 };
+	struct apk_indent indent;
 	int match = 0;
 
+	apk_print_indented_init(&indent, out, 0);
 	foreach_array_item(change, changeset->changes) {
-		if (!cmp(change))
-			continue;
-		if (match == 0)
-			printf("%s:\n", msg);
+		if (!cmp(change)) continue;
+		if (!match) apk_print_indented_group(&indent, 2, "%s:\n", msg);
 		if (change->new_pkg != NULL)
 			name = change->new_pkg->name;
 		else
@@ -149,8 +148,7 @@ static int dump_packages(struct apk_out *out, struct apk_changeset *changeset,
 		apk_print_indented(&indent, APK_BLOB_STR(name->name));
 		match++;
 	}
-	if (match)
-		printf("\n");
+	apk_print_indented_end(&indent);
 	return match;
 }
 
@@ -308,11 +306,11 @@ int apk_solver_commit_changeset(struct apk_database *db,
 					   "The following packages will be reinstalled");
 			if (download_size) {
 				size_unit = apk_get_human_size(download_size, &humanized);
-				printf("Need to download %lld %s of packages.\n",
+				apk_msg(out, "Need to download %lld %s of packages.",
 					(long long)humanized, size_unit);
 			}
 			size_unit = apk_get_human_size(llabs(size_diff), &humanized);
-			printf("After this operation, %lld %s of %s.\n",
+			apk_msg(out, "After this operation, %lld %s of %s.",
 				(long long)humanized,
 				size_unit,
 				(size_diff < 0) ?
@@ -405,22 +403,15 @@ struct print_state {
 static void label_start(struct print_state *ps, const char *text)
 {
 	if (ps->label) {
-		printf("  %s:\n", ps->label);
+		apk_print_indented_line(&ps->i, "  %s:\n", ps->label);
 		ps->label = NULL;
-		ps->i.x = ps->i.indent = 0;
 		ps->num_labels++;
 	}
-	if (ps->i.x == 0) {
-		ps->i.x = printf("    %s", text);
-		ps->i.indent = ps->i.x + 1;
-	}
+	if (!ps->i.x) apk_print_indented_group(&ps->i, 0, "    %s", text);
 }
 static void label_end(struct print_state *ps)
 {
-	if (ps->i.x != 0) {
-		printf("\n");
-		ps->i.x = ps->i.indent = 0;
-	}
+	apk_print_indented_end(&ps->i);
 }
 
 static void print_pinning_errors(struct print_state *ps, struct apk_package *pkg, unsigned int tag)
@@ -653,8 +644,6 @@ void apk_solver_print_errors(struct apk_database *db,
 	 * any other selected version. or all of them with -v.
 	 */
  
-	apk_err(out, "unable to select packages:");
-
 	/* Construct information about names */
 	foreach_array_item(change, changeset->changes) {
 		struct apk_package *pkg = change->new_pkg;
@@ -668,10 +657,11 @@ void apk_solver_print_errors(struct apk_database *db,
 
 	/* Analyze is package, and missing names referred to */
 	ps = (struct print_state) {
-		.i.out = out,
 		.db = db,
 		.world = world,
 	};
+	apk_err(out, "unable to select packages:");
+	apk_print_indented_init(&ps.i, out, 1);
 	analyze_deps(&ps, world);
 	foreach_array_item(change, changeset->changes) {
 		struct apk_package *pkg = change->new_pkg;
@@ -681,8 +671,8 @@ void apk_solver_print_errors(struct apk_database *db,
 		analyze_deps(&ps, pkg->depends);
 	}
 
-	if (ps.num_labels == 0)
-		printf("  Huh? Error reporter did not find the broken constraints.\n");
+	if (!ps.num_labels)
+		apk_print_indented_line(&ps.i, "Huh? Error reporter did not find the broken constraints.\n");
 }
 
 int apk_solver_commit(struct apk_database *db,

src/print.c

@@ -9,6 +9,7 @@
 
 #include <assert.h>
 #include <stdio.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <errno.h>
@@ -222,16 +223,52 @@ void apk_print_progress(struct apk_progress *p, size_t done, size_t total)
 	fputs("\e8\e[0K", out);
 }
 
+void apk_print_indented_init(struct apk_indent *i, struct apk_out *out, int err)
+{
+	*i = (struct apk_indent) {
+		.f = err ? out->err : out->out,
+		.width = apk_out_get_width(out),
+	};
+	out->last_change++;
+}
+
+void apk_print_indented_line(struct apk_indent *i, const char *fmt, ...)
+{
+	va_list va;
+
+	va_start(va, fmt);
+	vfprintf(i->f, fmt, va);
+	va_end(va);
+	i->x = i->indent = 0;
+}
+
+void apk_print_indented_group(struct apk_indent *i, int indent, const char *fmt, ...)
+{
+	va_list va;
+
+	va_start(va, fmt);
+	i->x = vfprintf(i->f, fmt, va);
+	i->indent = indent ?: (i->x + 1);
+	if (fmt[strlen(fmt)-1] == '\n') i->x = 0;
+	va_end(va);
+}
+
+void apk_print_indented_end(struct apk_indent *i)
+{
+	if (i->x) {
+		fprintf(i->f, "\n");
+		i->x = i->indent = 0;
+	}
+}
+
 int apk_print_indented(struct apk_indent *i, apk_blob_t blob)
 {
-	FILE *out = i->out->out;
 	if (i->x <= i->indent)
-		i->x += fprintf(out, "%*s" BLOB_FMT, i->indent - i->x, "", BLOB_PRINTF(blob));
-	else if (i->x + blob.len + 1 >= apk_out_get_width(i->out))
-		i->x = fprintf(out, "\n%*s" BLOB_FMT, i->indent, "", BLOB_PRINTF(blob)) - 1;
+		i->x += fprintf(i->f, "%*s" BLOB_FMT, i->indent - i->x, "", BLOB_PRINTF(blob));
+	else if (i->x + blob.len + 1 >= i->width)
+		i->x = fprintf(i->f, "\n%*s" BLOB_FMT, i->indent, "", BLOB_PRINTF(blob)) - 1;
 	else
-		i->x += fprintf(out, " " BLOB_FMT, BLOB_PRINTF(blob));
-	i->out->last_change++;
+		i->x += fprintf(i->f, " " BLOB_FMT, BLOB_PRINTF(blob));
 	return 0;
 }