gh-608 Initial implementation of sample spec parser

src/internal_modules/roc_audio/channel_defs.cpp

@@ -56,16 +56,6 @@ const char* channel_pos_to_str(ChannelPosition pos) {
     return NULL;
 }
 
-ChannelPosition channel_pos_from_str(const char* name) {
-    for (size_t i = 0; i < ROC_ARRAY_SIZE(ChanPositionNames); i++) {
-        if (strcmp(ChanPositionNames[i].name, name) == 0) {
-            return ChanPositionNames[i].pos;
-        }
-    }
-
-    return ChanPos_Max;
-}
-
 const char* channel_mask_to_str(ChannelMask mask) {
     for (size_t i = 0; i < ROC_ARRAY_SIZE(ChanMaskNames); i++) {
         if (ChanMaskNames[i].mask == mask) {
@@ -76,15 +66,5 @@ const char* channel_mask_to_str(ChannelMask mask) {
     return NULL;
 }
 
-ChannelMask channel_mask_from_str(const char* name) {
-    for (size_t i = 0; i < ROC_ARRAY_SIZE(ChanMaskNames); i++) {
-        if (strcmp(ChanMaskNames[i].name, name) == 0) {
-            return ChanMaskNames[i].mask;
-        }
-    }
-
-    return 0;
-}
-
 } // namespace audio
 } // namespace roc

src/internal_modules/roc_audio/channel_defs.h

@@ -388,15 +388,9 @@ const char* channel_order_to_str(ChannelOrder);
 //! Get string name from channel position.
 const char* channel_pos_to_str(ChannelPosition);
 
-//! Get channel position from string name.
-ChannelPosition channel_pos_from_str(const char*);
-
 //! Get string name from channel mask.
 const char* channel_mask_to_str(ChannelMask);
 
-//! Get channel mask from string name.
-ChannelMask channel_mask_from_str(const char*);
-
 } // namespace audio
 } // namespace roc
 

src/internal_modules/roc_audio/channel_set.cpp

@@ -153,6 +153,14 @@ size_t ChannelSet::last_channel() const {
     return last_chan_;
 }
 
+bool ChannelSet::is_equal(ChannelMask mask) const {
+    if (last_chan_ >= WordBits) {
+        return false;
+    }
+
+    return (words_[0] == mask);
+}
+
 bool ChannelSet::is_subset(ChannelMask mask) const {
     if (last_chan_ >= WordBits) {
         return false;

src/internal_modules/roc_audio/channel_set.h

@@ -83,6 +83,12 @@ class ChannelSet {
     //!  Panics if there are no enabled channels.
     size_t last_channel() const;
 
+    //! Check if channel set is equal to given mask.
+    //! @remarks
+    //!  The mask defines only first 32 channels. If any channels outside of 0-31
+    //!  range are enabled in channel set, the method will fail.
+    bool is_equal(ChannelMask mask) const;
+
     //! Check if channel set is sub-set of given mask, or equal to it.
     //! @remarks
     //!  The mask defines only first 32 channels. If any channels outside of 0-31

src/internal_modules/roc_audio/channel_set_format.cpp

@@ -39,27 +39,26 @@ void format_channel_set(const ChannelSet& ch_set, core::StringBuilder& bld) {
         } else {
             bld.append_str(" ch=0x");
 
-            // Find last non-zero byte.
             size_t last_byte = 0;
+
             for (size_t n = 0; n < ch_set.num_bytes(); n++) {
                 if (ch_set.byte_at(n) != 0) {
                     last_byte = n;
                 }
             }
 
-            // Format bitmask from LSB to MSB in hex.
-            for (size_t n = 0; n <= last_byte; n++) {
+            size_t n = last_byte;
+            do {
                 const uint8_t byte = ch_set.byte_at(n);
 
                 const uint8_t lo = (byte & 0xf);
                 const uint8_t hi = ((byte >> 4) & 0xf);
 
-                bld.append_uint(lo, 16);
-
                 if (hi != 0 || n != last_byte) {
                     bld.append_uint(hi, 16);
                 }
-            }
+                bld.append_uint(lo, 16);
+            } while (n-- != 0);
         }
     }
 

src/internal_modules/roc_audio/sample_spec.cpp

@@ -97,6 +97,11 @@ bool SampleSpec::is_valid() const {
     return sample_rate_ != 0 && channel_set_.is_valid();
 }
 
+void SampleSpec::clear() {
+    sample_rate_ = 0;
+    channel_set_.clear();
+}
+
 size_t SampleSpec::sample_rate() const {
     return sample_rate_;
 }

src/internal_modules/roc_audio/sample_spec.h

@@ -15,6 +15,7 @@
 #include "roc_audio/channel_set.h"
 #include "roc_audio/sample.h"
 #include "roc_core/stddefs.h"
+#include "roc_core/string_builder.h"
 #include "roc_core/time.h"
 #include "roc_packet/units.h"
 
@@ -57,6 +58,9 @@ class SampleSpec {
     //! Check if sample spec has non-zero rate and valid channel set.
     bool is_valid() const;
 
+    //! Unset all fields.
+    void clear();
+
     //! Get sample rate.
     //! @remarks
     //!  Defines sample frequency (number of samples per second).
@@ -148,6 +152,12 @@ class SampleSpec {
     ChannelSet channel_set_;
 };
 
+//! Parse sample spec from string.
+bool parse_sample_spec(const char* str, SampleSpec& result);
+
+//! Format sample spec to string.
+void format_sample_spec(const SampleSpec& sample_spec, core::StringBuilder& bld);
+
 } // namespace audio
 } // namespace roc
 

src/internal_modules/roc_audio/sample_spec_format.cpp

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2023 Roc Streaming authors
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include "roc_audio/sample_spec.h"
+
+namespace roc {
+namespace audio {
+
+void format_sample_spec(const SampleSpec& sample_spec, core::StringBuilder& bld) {
+    bld.append_str("<sspec rate=");
+    bld.append_uint(sample_spec.sample_rate(), 10);
+    bld.append_str(" chset=");
+    format_channel_set(sample_spec.channel_set(), bld);
+    bld.append_str(">");
+}
+
+} // namespace audio
+} // namespace roc