fftools/textformat: Introduce common header and deduplicate code

Also change writer_printf signature in AVTextWriter to use va_list,
so that it can be called by the new function writer_printf()
in tf_internal.h.

Reviewed-by: Stefano Sabatini <stefasab@gmail.com>
Signed-off-by: softworkz <softworkz@hotmail.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/fftools/textformat/tf_internal.h b/fftools/textformat/tf_internal.h
new file mode 100644
index 0000000000..362a4cbc38
--- /dev/null
+++ b/fftools/textformat/tf_internal.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) The FFmpeg developers
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Internal utilities for text formatters.
+ */
+
+#ifndef FFTOOLS_TEXTFORMAT_TF_INTERNAL_H
+#define FFTOOLS_TEXTFORMAT_TF_INTERNAL_H
+
+#include "avtextformat.h"
+
+#define DEFINE_FORMATTER_CLASS(name)                \
+static const char *name##_get_name(void *ctx)       \
+{                                                   \
+    return #name ;                                  \
+}                                                   \
+static const AVClass name##_class = {               \
+    .class_name = #name,                            \
+    .item_name  = name##_get_name,                  \
+    .option     = name##_options                    \
+}
+
+
+/**
+ * Safely validate and access a section at a given level
+ */
+static inline const AVTextFormatSection *tf_get_section(AVTextFormatContext *tfc, int level)
+{
+    if (!tfc || level < 0 || level >= SECTION_MAX_NB_LEVELS || !tfc->section[level]) {
+        if (tfc)
+            av_log(tfc, AV_LOG_ERROR, "Invalid section access at level %d\n", level);
+        return NULL;
+    }
+    return tfc->section[level];
+}
+
+/**
+ * Safely access the parent section
+ */
+static inline const AVTextFormatSection *tf_get_parent_section(AVTextFormatContext *tfc, int level)
+{
+    if (level <= 0)
+        return NULL;
+
+    return tf_get_section(tfc, level - 1);
+}
+
+static inline void writer_w8(AVTextFormatContext *wctx, int b)
+{
+    wctx->writer->writer->writer_w8(wctx->writer, b);
+}
+
+static inline void writer_put_str(AVTextFormatContext *wctx, const char *str)
+{
+    wctx->writer->writer->writer_put_str(wctx->writer, str);
+}
+
+static inline void writer_printf(AVTextFormatContext *wctx, const char *fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    wctx->writer->writer->writer_vprintf(wctx->writer, fmt, args);
+    va_end(args);
+}
+
+#endif /* FFTOOLS_TEXTFORMAT_TF_INTERNAL_H */