libcamera: bayer_format: Add operator<<()

Implement the stream output operator<<() for the BayerFormat class to
simplify printing them.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

2 files changed, 39 insertions, 21 deletions

diff --git a/include/libcamera/internal/bayer_format.h b/include/libcamera/internal/bayer_format.h
index cb20bf9b..7d3e37c6 100644
--- a/include/libcamera/internal/bayer_format.h
+++ b/include/libcamera/internal/bayer_format.h
@@ -7,6 +7,7 @@
 
 #pragma once
 
+#include <ostream>
 #include <stdint.h>
 #include <string>
 
@@ -68,4 +69,6 @@ static inline bool operator!=(const BayerFormat &lhs, const BayerFormat &rhs)
 	return !(lhs == rhs);
 }
 
+std::ostream &operator<<(std::ostream &out, const BayerFormat &f);
+
 } /* namespace libcamera */
diff --git a/src/libcamera/bayer_format.cpp b/src/libcamera/bayer_format.cpp
index 9aaec0bc..4882707e 100644
--- a/src/libcamera/bayer_format.cpp
+++ b/src/libcamera/bayer_format.cpp
@@ -9,6 +9,7 @@
 
 #include <algorithm>
 #include <map>
+#include <sstream>
 #include <unordered_map>
 
 #include <linux/media-bus-format.h>
@@ -236,28 +237,10 @@ const BayerFormat &BayerFormat::fromMbusCode(unsigned int mbusCode)
  */
 std::string BayerFormat::toString() const
 {
-	std::string result;
+	std::stringstream ss;
+	ss << *this;
 
-	static const char *orderStrings[] = {
-		"BGGR",
-		"GBRG",
-		"GRBG",
-		"RGGB",
-		"MONO"
-	};
-	if (isValid() && order <= MONO)
-		result = orderStrings[order];
-	else
-		return "INVALID";
-
-	result += "-" + std::to_string(bitDepth);
-
-	if (packing == Packing::CSI2)
-		result += "-CSI2P";
-	else if (packing == Packing::IPU3)
-		result += "-IPU3P";
-
-	return result;
+	return ss.str();
 }
 
 /**
@@ -271,6 +254,38 @@ bool operator==(const BayerFormat &lhs, const BayerFormat &rhs)
 }
 
 /**
+ * \brief Insert a text representation of a BayerFormats into an output stream
+ * \param[in] out The output stream
+ * \param[in] f The BayerFormat
+ * \return The output stream \a out
+ */
+std::ostream &operator<<(std::ostream &out, const BayerFormat &f)
+{
+	static const char *orderStrings[] = {
+		"BGGR-",
+		"GBRG-",
+		"GRBG-",
+		"RGGB-",
+		"MONO-"
+	};
+
+	if (!f.isValid() || f.order > BayerFormat::MONO) {
+		out << "INVALID";
+		return out;
+	}
+
+	/* The cast is required to avoid bitDepth being interpreted as a char. */
+	out << orderStrings[f.order] << static_cast<unsigned int>(f.bitDepth);
+
+	if (f.packing == BayerFormat::Packing::CSI2)
+		out << "-CSI2P";
+	else if (f.packing == BayerFormat::Packing::IPU3)
+		out << "-IPU3P";
+
+	return out;
+}
+
+/**
  * \fn bool operator!=(const BayerFormat &lhs, const BayerFormat &rhs)
  * \brief Compare two BayerFormats for inequality
  * \return True if either order, bitdepth or packing are not equal, or false