Compiling the core library on Linux(ubuntu)

[idykman]

trying to compile the core lib under ubuntu using https://github.com/breadwallet/breadwallet-core/blob/master/Java/Core/CMakeLists.txt and facing several problems:

1. core/support/BRAssert.c:196:42: error: ‘PTHREAD_MUTEX_RECURSIVE’ undeclared
   Solved by CFLAG _XOPEN_SOURCE=600

2. core/support/BRFileService.c:286:33: error: ‘DT_REG’ undeclared (first use in this function)
   Solved by CFLAG _GNU_SOURCE

3. Required code change:
   core/support/BRAssert.c:138:5: error: too few arguments to function ‘pthread_setname_np’

core/src/main/cpp/core/support/BRInt.h:138:31: error: initializer element is not constant
#define uint256(s) ((UInt256) { .u8 = {
^
Can you help me with those issues? Thanks!

[michael-brd]

Hi @idykman, how are you trying to build? Could you outline what your steps are here?

[idykman]

I'm building using provided CMakeList.txt using default gcc, cmake and make installation on Ubuntu 18.04. My only changes to CMakeList.txt so far are related to flags I've mentioned in OP.
Build process is very simple:
cd Java/Core
mkdir build
cmake .. && make

[idykman]

Just in case, below is the diff:

--- a/Java/Core/CMakeLists.txt
+++ b/Java/Core/CMakeLists.txt
@@ -6,7 +6,7 @@
 cmake_minimum_required(VERSION 3.4.1)
 
 # now build app's shared lib
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -DANDROID_STL=gnustl_static -DANDROID_TOOLCHAIN=clang")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -D_GNU_SOURCE -D_XOPEN_SOURCE=600 -D__LINUX__ -DANDROID_STL=gnustl_static -DANDROID_TOOLCHAIN=clang")
 
 # -Wimplicit-function-declaration
 # -Wno-missing-prototypes -Werror=return-type -Wdocumentation -Wunreachable-code-aggressive -Wno-missing-braces
@@ -297,12 +297,12 @@ include_directories(src/main/cpp/core/secp256k1/)
 # you want to add. CMake verifies that the library exists before
 # completing its build.
 
-find_library( # Sets the name of the path variable.
-              log-lib
+#find_library( # Sets the name of the path variable.
+#              log-lib
 
               # Specifies the name of the NDK library that
               # you want CMake to locate.
-              log )
+              #log)
 
 # Specifies libraries CMake should link to your target library. You
 # can link multiple libraries, such as libraries you define in this
@@ -313,4 +313,5 @@ target_link_libraries( # Specifies the target library.
 
                        # Links the target library to the log library
                        # included in the NDK.
-                       ${log-lib} )
\ No newline at end of file
+                       #${log-lib} 
+)
diff --git a/support/BRAssert.c b/support/BRAssert.c
index 49542d2..cc42232 100644
--- a/support/BRAssert.c
+++ b/support/BRAssert.c
@@ -132,7 +132,7 @@ typedef void* (*ThreadRoutine) (void*);         // pthread_create
 
 static void *
 BRAssertThread (BRAssertContext *context) {
-#if defined (__ANDROID__)
+#if defined (__ANDROID__) || defined (__LINUX__)
     pthread_setname_np (context->thread, ASSERT_THREAD_NAME);
 #else
     pthread_setname_np (ASSERT_THREAD_NAME);

[michael-brd]

We build for Android using Android Studio and for iOS via XCode (in the breadwallet-ios project).

So we don't officially build for Linux (per say) but I will take a look next week at seeing if I can get a build going.

[idykman]

@michael-brd Just FYI:
This error:

BRInt.h:138:31: error: initializer element is not constant

boil down to the fact that linux gcc is not happy about following initialization:

test.c:6:19: error: initializer element is not constant
static char xxx = "abc"[0];
                  ^

From the recent C11 draft (it did not change from C99):

An address constant is a null pointer, a pointer to an lvalue
designating an object of static storage duration, or a pointer to a
function designator; it shall be created explicitly using the unary &
operator or an integer constant cast to pointer type, or implicitly by
the use of an expression of array or function type. The
array-subscript [] and member-access . and -> operators, the address
& and indirection * unary operators, and pointer casts may be used in
the creation of an address constant, but the value of an object shall
not be accessed by use of these operators.

[michael-brd]

Thanks @idykman. It sounds like you are able to build now, correct? I'll log a ticket to get this addressed.

[idykman]

No, I'm not. I mentioned the root cause of the problem, but not a fix unfortunately. Your help is still needed and appreciated.

…

On Tue, May 21, 2019, 04:57 michael-brd ***@***.***> wrote: Thanks @idykman <https://github.com/idykman>. It sounds like you are able to build now, correct? I'll log a ticket to get this addressed. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#45?email_source=notifications&email_token=AHZMCJGHWUK3UHXMRD2P4ZTPWPPRNA5CNFSM4HNXVD6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODV3VMBY#issuecomment-494360071>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AHZMCJDL5DPW3YOVQVLYIULPWPPRNANCNFSM4HNXVD6A> .

[michael-brd]

I built on Ubuntu x64 18.04 by doing the following:

• Installing cmake and clang-7
• Making the changes included below
• Running "cd Java/Core && cmake . -DCMAKE_C_COMPILER=clang-7 -DCMAKE_CXX_COMPILER=clang++-7"
• Running "make"

This builds using clang (instead of GCC), which is what is used by the Android and iOS builds. In addition, it removes the JNI files (which aren't relevant if you are just trying to use the C functionality). Finally, it fixes some portability issues (i.e. preprocessor guards, includes, etc.).

Let me know if you have any issues.

---

diff --git a/Java/Core/CMakeLists.txt b/Java/Core/CMakeLists.txt
index 6a2c8ac1..44fdc8f9 100644
--- a/Java/Core/CMakeLists.txt
+++ b/Java/Core/CMakeLists.txt
@@ -6,7 +6,7 @@
 cmake_minimum_required(VERSION 3.4.1)
 
 # now build app's shared lib
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -DANDROID_STL=gnustl_static -DANDROID_TOOLCHAIN=clang")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -D_GNU_SOURCE")
 
 # -Wimplicit-function-declaration
 # -Wno-missing-prototypes -Werror=return-type -Wdocumentation -Wunreachable-code-aggressive -Wno-missing-braces
@@ -82,38 +82,6 @@ target_sources (core
                 src/main/cpp/core/bcash/BRBCashParams.c
                 )
 
-# Core JNI
-target_sources (core
-                PUBLIC
-                src/main/cpp/jni/BRCoreJni.h
-                src/main/cpp/jni/BRCoreJni.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreJniReference.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreJniReference.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreAddress.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreAddress.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreChainParams.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreChainParams.h
-                src/main/cpp/jni/com_breadwallet_core_BRCorePeer.c
-                src/main/cpp/jni/com_breadwallet_core_BRCorePeer.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreMasterPubKey.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreMasterPubKey.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreKey.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreKey.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreMerkleBlock.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreMerkleBlock.h
-                src/main/cpp/jni/com_breadwallet_core_BRCorePeerManager.c
-                src/main/cpp/jni/com_breadwallet_core_BRCorePeerManager.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreTransaction.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreTransaction.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreTransactionInput.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreTransactionInput.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreTransactionOutput.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreTransactionOutput.h
-                src/main/cpp/jni/com_breadwallet_core_BRCorePaymentProtocol.c
-                src/main/cpp/jni/com_breadwallet_core_BRCorePaymentProtocol.h
-                src/main/cpp/jni/com_breadwallet_core_BRCoreWallet.c
-                src/main/cpp/jni/com_breadwallet_core_BRCoreWallet.h)
-
 # Core Ethereum
 target_sources (core
                 PUBLIC
@@ -262,21 +230,6 @@ target_sources (core
 #                src/main/cpp/core/ethereum/ewm/testEwm.c
                 )
 
-# Core Ethereum JNI
-target_sources (core
-                PUBLIC
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumAccount.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumAmount.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumBlock.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumEWM.c
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumEWM.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumNetwork.c
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumNetwork.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumToken.c
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumToken.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumTransaction.h
-                src/main/cpp/jni/ethereum/com_breadwallet_core_ethereum_BREthereumWallet.h)
-
 include_directories(src/main/cpp/core/)
 include_directories(src/main/cpp/core/support)
 include_directories(src/main/cpp/core/bitcoin)
@@ -290,20 +243,7 @@ include_directories(src/main/cpp/core/secp256k1/)
 # you want to add. CMake verifies that the library exists before
 # completing its build.
 
-find_library( # Sets the name of the path variable.
-              log-lib
-
-              # Specifies the name of the NDK library that
-              # you want CMake to locate.
-              log )
-
 # Specifies libraries CMake should link to your target library. You
 # can link multiple libraries, such as libraries you define in this
 # build script, prebuilt third-party libraries, or system libraries.
 
-target_link_libraries( # Specifies the target library.
-                       core
-
-                       # Links the target library to the log library
-                       # included in the NDK.
-                       ${log-lib} )
\ No newline at end of file
diff --git a/ethereum/event/BREvent.c b/ethereum/event/BREvent.c
index 774466c6..16a5be1e 100644
--- a/ethereum/event/BREvent.c
+++ b/ethereum/event/BREvent.c
@@ -174,7 +174,7 @@ typedef void* (*ThreadRoutine) (void*);
 static void *
 eventHandlerThread (BREventHandler handler) {
 
-#if defined (__ANDROID__)
+#if defined (__ANDROID__) || defined(__linux__)
     pthread_setname_np(handler->thread, handler->name);
 #else
     pthread_setname_np(handler->name);
diff --git a/ethereum/event/BREventAlarm.c b/ethereum/event/BREventAlarm.c
index f103c037..7eeca70f 100644
--- a/ethereum/event/BREventAlarm.c
+++ b/ethereum/event/BREventAlarm.c
@@ -260,7 +260,7 @@ typedef void* (*ThreadRoutine) (void*);
 static void *
 alarmClockThread (BREventAlarmClock clock) {
 
-#if defined (__ANDROID__)
+#if defined (__ANDROID__) || defined(__linux__)
     pthread_setname_np(clock->thread, "Core Ethereum Alarm Clock");
 #else
     pthread_setname_np("Core Ethereum Alarm Clock");
diff --git a/ethereum/les/BREthereumLES.c b/ethereum/les/BREthereumLES.c
index 14dede4d..d3b1337a 100644
--- a/ethereum/les/BREthereumLES.c
+++ b/ethereum/les/BREthereumLES.c
@@ -1122,7 +1122,7 @@ lesThreadBootstrapSeeds (BREthereumLES les) {
 
 static void *
 lesThread (BREthereumLES les) {
-#if defined (__ANDROID__)
+#if defined (__ANDROID__) || (__linux__)
     pthread_setname_np (les->thread, LES_THREAD_NAME);
 #else
     pthread_setname_np (LES_THREAD_NAME);
diff --git a/ethereum/util/BRUtilHex.h b/ethereum/util/BRUtilHex.h
index 46f4e21b..3a8c6f0f 100644
--- a/ethereum/util/BRUtilHex.h
+++ b/ethereum/util/BRUtilHex.h
@@ -12,6 +12,7 @@
 #define BR_Util_Hex_H
 
 #include <stdlib.h>
+#include <stdint.h>
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/support/BRAssert.c b/support/BRAssert.c
index 49542d26..dd4e641f 100644
--- a/support/BRAssert.c
+++ b/support/BRAssert.c
@@ -132,7 +132,7 @@ typedef void* (*ThreadRoutine) (void*);         // pthread_create
 
 static void *
 BRAssertThread (BRAssertContext *context) {
-#if defined (__ANDROID__)
+#if defined (__ANDROID__) || defined (__linux__)
     pthread_setname_np (context->thread, ASSERT_THREAD_NAME);
 #else
     pthread_setname_np (ASSERT_THREAD_NAME);`

[idykman]

This works, thanks a lot for the solution! Are you planning to make .c and .h changes in this repo? It will help us with future integraions

[michael-brd]

Yes, this repository undergoes regular feature development.

That said, we've create a ticket in our system to look at creating a supported Linux build. The idea being we keep that working as changes are made.

[piqjen-1xofFi-sikxyh]

Where was this build originally from

[piqjen-1xofFi-sikxyh]

Jennifer Warren's