libcamera: Fix build with clang-18

Signed-off-by: Khem Raj <raj.khem@gmail.com>

3 files changed, 152 insertions, 0 deletions

diff --git a/meta-multimedia/recipes-multimedia/libcamera/libcamera/0001-media_device-Add-bool-return-type-to-unlock.patch b/meta-multimedia/recipes-multimedia/libcamera/libcamera/0001-media_device-Add-bool-return-type-to-unlock.patch
new file mode 100644
index 000000000..12f034eff
--- /dev/null
+++ b/meta-multimedia/recipes-multimedia/libcamera/libcamera/0001-media_device-Add-bool-return-type-to-unlock.patch
@@ -0,0 +1,59 @@
+From 6914c4fd3d53c0c6ea304123bf57429bb64ec16f Mon Sep 17 00:00:00 2001
+From: Khem Raj <raj.khem@gmail.com>
+Date: Wed, 31 Jan 2024 21:01:27 -0800
+Subject: [PATCH 1/2] media_device: Add bool return type to unlock()
+
+unlock uses lockf which is marked with __attribute__
+((warn_unused_result)) and compilers warn about it and some treat
+-Wunused-result as error with -Werror turned on, It would be good to
+check if lockf failed or succeeded, however, that piece is not changed
+with this, this fixes build with clang++ 18
+
+    ../git/src/libcamera/media_device.cpp:167:2: error: ignoring return value of function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result]
+      167 |         lockf(fd_.get(), F_ULOCK, 0);
+          |         ^~~~~ ~~~~~~~~~~~~~~~~~~~~~
+    1 error generated.
+
+Upstream-Status: Submitted [https://lists.libcamera.org/pipermail/libcamera-devel/2024-February/040380.html]
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ include/libcamera/internal/media_device.h | 2 +-
+ src/libcamera/media_device.cpp            | 6 +++---
+ 2 files changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/include/libcamera/internal/media_device.h b/include/libcamera/internal/media_device.h
+index eb8cfde4..b09dfd16 100644
+--- a/include/libcamera/internal/media_device.h
++++ b/include/libcamera/internal/media_device.h
+@@ -33,7 +33,7 @@ public:
+        bool busy() const { return acquired_; }
+ 
+        bool lock();
+-       void unlock();
++       bool unlock();
+ 
+        int populate();
+        bool isValid() const { return valid_; }
+diff --git a/src/libcamera/media_device.cpp b/src/libcamera/media_device.cpp
+index 2949816b..eaa2fdb0 100644
+--- a/src/libcamera/media_device.cpp
++++ b/src/libcamera/media_device.cpp
+@@ -159,12 +159,12 @@ bool MediaDevice::lock()
+  *
+  * \sa lock()
+  */
+-void MediaDevice::unlock()
++bool MediaDevice::unlock()
+ {
+        if (!fd_.isValid())
+-               return;
++               return false;
+ 
+-       lockf(fd_.get(), F_ULOCK, 0);
++       return lockf(fd_.get(), F_ULOCK, 0) == 0;
+ }
+ 
+ /**
+-- 
+2.43.0
+
diff --git a/meta-multimedia/recipes-multimedia/libcamera/libcamera/0002-options-Replace-use-of-VLAs-in-C.patch b/meta-multimedia/recipes-multimedia/libcamera/libcamera/0002-options-Replace-use-of-VLAs-in-C.patch
new file mode 100644
index 000000000..95f321782
--- /dev/null
+++ b/meta-multimedia/recipes-multimedia/libcamera/libcamera/0002-options-Replace-use-of-VLAs-in-C.patch
@@ -0,0 +1,91 @@
+From c80d273a57547aec9353d888aa316bf6560cf1ba Mon Sep 17 00:00:00 2001
+From: Khem Raj <raj.khem@gmail.com>
+Date: Wed, 31 Jan 2024 21:04:28 -0800
+Subject: [PATCH 2/2] options: Replace use of VLAs in C++
+
+Clang++ 18 is fussy about this with new warning checks.
+
+   ../git/src/apps/common/options.cpp:882:20: error: variable length arrays in C++ are a Clang extension [-Werror,-Wvla-cxx-extension]
+      882 |         char shortOptions[optionsMap_.size() * 3 + 2];
+          |                           ^~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Therefore replace using VLAs with alloca and malloc/free
+
+Upstream-Status: Submitted [https://lists.libcamera.org/pipermail/libcamera-devel/2024-February/040381.html]
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ src/apps/common/options.cpp      |  4 ++--
+ src/libcamera/ipc_unixsocket.cpp | 12 ++++++++----
+ 2 files changed, 10 insertions(+), 6 deletions(-)
+
+diff --git a/src/apps/common/options.cpp b/src/apps/common/options.cpp
+index 4f7e8691..b020f603 100644
+--- a/src/apps/common/options.cpp
++++ b/src/apps/common/options.cpp
+@@ -879,8 +879,8 @@ OptionsParser::Options OptionsParser::parse(int argc, char **argv)
+         * Allocate short and long options arrays large enough to contain all
+         * options.
+         */
+-       char shortOptions[optionsMap_.size() * 3 + 2];
+-       struct option longOptions[optionsMap_.size() + 1];
++       char *shortOptions = (char*)alloca(optionsMap_.size() * 3 + 2);
++       struct option *longOptions = (struct option*)alloca(optionsMap_.size() + 1);
+        unsigned int ids = 0;
+        unsigned int idl = 0;
+ 
+diff --git a/src/libcamera/ipc_unixsocket.cpp b/src/libcamera/ipc_unixsocket.cpp
+index 1980d374..3a7f8ee6 100644
+--- a/src/libcamera/ipc_unixsocket.cpp
++++ b/src/libcamera/ipc_unixsocket.cpp
+@@ -247,8 +247,8 @@ int IPCUnixSocket::sendData(const void *buffer, size_t length,
+        iov[0].iov_base = const_cast<void *>(buffer);
+        iov[0].iov_len = length;
+ 
+-       char buf[CMSG_SPACE(num * sizeof(uint32_t))];
+-       memset(buf, 0, sizeof(buf));
++       char *buf = (char*)malloc(CMSG_SPACE(num * sizeof(uint32_t)));
++       memset((void*)buf, 0, sizeof(buf));
+ 
+        struct cmsghdr *cmsg = (struct cmsghdr *)buf;
+        cmsg->cmsg_len = CMSG_LEN(num * sizeof(uint32_t));
+@@ -270,9 +270,11 @@ int IPCUnixSocket::sendData(const void *buffer, size_t length,
+                int ret = -errno;
+                LOG(IPCUnixSocket, Error)
+                        << "Failed to sendmsg: " << strerror(-ret);
++    free(buf);
+                return ret;
+        }
+ 
++  free(buf);
+        return 0;
+ }
+ 
+@@ -283,8 +285,8 @@ int IPCUnixSocket::recvData(void *buffer, size_t length,
+        iov[0].iov_base = buffer;
+        iov[0].iov_len = length;
+ 
+-       char buf[CMSG_SPACE(num * sizeof(uint32_t))];
+-       memset(buf, 0, sizeof(buf));
++       char *buf = (char*)malloc(CMSG_SPACE(num * sizeof(uint32_t)));
++       memset((void*)buf, 0, sizeof(buf));
+ 
+        struct cmsghdr *cmsg = (struct cmsghdr *)buf;
+        cmsg->cmsg_len = CMSG_LEN(num * sizeof(uint32_t));
+@@ -305,12 +307,14 @@ int IPCUnixSocket::recvData(void *buffer, size_t length,
+                if (ret != -EAGAIN)
+                        LOG(IPCUnixSocket, Error)
+                                << "Failed to recvmsg: " << strerror(-ret);
++    free(buf);
+                return ret;
+        }
+ 
+        if (fds)
+                memcpy(fds, CMSG_DATA(cmsg), num * sizeof(uint32_t));
+ 
++  free(buf);
+        return 0;
+ }
+ 
+-- 
+2.43.0
+
diff --git a/meta-multimedia/recipes-multimedia/libcamera/libcamera_0.2.0.bb b/meta-multimedia/recipes-multimedia/libcamera/libcamera_0.2.0.bb
index 3fd17f0a8..5b2e86336 100644
--- a/meta-multimedia/recipes-multimedia/libcamera/libcamera_0.2.0.bb
+++ b/meta-multimedia/recipes-multimedia/libcamera/libcamera_0.2.0.bb
@@ -10,6 +10,8 @@ LIC_FILES_CHKSUM = "\
 
 SRC_URI = " \
         git://git.libcamera.org/libcamera/libcamera.git;protocol=https;branch=master \
+        file://0001-media_device-Add-bool-return-type-to-unlock.patch \
+        file://0002-options-Replace-use-of-VLAs-in-C.patch \
 "
 
 SRCREV = "89227a428a82e724548399d35c98ea89566f9045"