Merge branch 'bundled-sqlite'

Improve using bundled SQLite.

See #1243.

cmake/soci_compiler_options.cmake

@@ -31,16 +31,24 @@ if (WIN32)
   )
 endif()
 
+# We want to use warning-related options only for C++ source files (this
+# excludes 3rdparty/sqlite3/sqlite3.c) and only when compiling SOCI itself and
+# not an application using it.
+set(soci_cxx_source "$<AND:$<BOOL:${PROJECT_IS_TOP_LEVEL}>,$<COMPILE_LANGUAGE:CXX>>")
+
 if (MSVC)
   # Configure warnings
   target_compile_options(soci_compiler_interface
     INTERFACE
-      "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:/W4>"
-      "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:/we4266>"
+      "$<${soci_cxx_source}:/W4>"
+      "$<${soci_cxx_source}:/we4266>"
   )
 
   if (SOCI_ENABLE_WERROR)
-    target_compile_options(soci_compiler_interface INTERFACE "/WX")
+    target_compile_options(soci_compiler_interface
+      INTERFACE
+        "$<${soci_cxx_source}:/WX>"
+    )
   endif()
 
   if (SOCI_LD)
@@ -51,7 +59,10 @@ if (MSVC)
 else()
 
   if (SOCI_ENABLE_WERROR)
-    target_compile_options(soci_compiler_interface INTERFACE "-Werror")
+    target_compile_options(soci_compiler_interface
+      INTERFACE
+        "$<${soci_cxx_source}:-Werror>"
+    )
   endif()
 
   if (SOCI_UBSAN)
@@ -87,29 +98,29 @@ else()
 
     if (CMAKE_COMPILER_IS_GNUCXX)
       if (NOT (CMAKE_SYSTEM_NAME MATCHES "FreeBSD"))
-        target_compile_options(soci_compiler_interface INTERFACE "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wno-variadic-macros>")
+        target_compile_options(soci_compiler_interface INTERFACE "$<${soci_cxx_source}:-Wno-variadic-macros>")
       endif()
     endif()
 
     set(SOCI_USE_STD_FLAGS ON)
   else()
-	  message(WARNING "Unknown toolset - using default flags to build SOCI")
+    message(WARNING "Unknown toolset - using default flags to build SOCI")
   endif()
 
   if (SOCI_USE_STD_FLAGS)
     target_compile_options(soci_compiler_interface
       INTERFACE
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-pedantic>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wno-error=parentheses>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wall>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wextra>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wpointer-arith>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wcast-align>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wcast-qual>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wfloat-equal>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Woverloaded-virtual>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wredundant-decls>"
-        "$<$<BOOL:${PROJECT_IS_TOP_LEVEL}>:-Wno-long-long>"
+        "$<${soci_cxx_source}:-pedantic>"
+        "$<${soci_cxx_source}:-Wno-error=parentheses>"
+        "$<${soci_cxx_source}:-Wall>"
+        "$<${soci_cxx_source}:-Wextra>"
+        "$<${soci_cxx_source}:-Wpointer-arith>"
+        "$<${soci_cxx_source}:-Wcast-align>"
+        "$<${soci_cxx_source}:-Wcast-qual>"
+        "$<${soci_cxx_source}:-Wfloat-equal>"
+        "$<${soci_cxx_source}:-Woverloaded-virtual>"
+        "$<${soci_cxx_source}:-Wredundant-decls>"
+        "$<${soci_cxx_source}:-Wno-long-long>"
     )
   endif()
 endif()

cmake/soci_define_backend_target.cmake

@@ -67,6 +67,11 @@ function(soci_define_backend_target)
   string(TOUPPER "${DEFINE_BACKEND_NAME}" BACKEND_UPPER)
   set(DEFINE_BACKEND_ENABLED_VARIABLE "SOCI_${BACKEND_UPPER}")
 
+  # Skip looking for dependencies if built-in version is preferred.
+  if (${SOCI_${BACKEND_UPPER}_BUILTIN})
+    unset(DEFINE_BACKEND_DEPENDENCIES)
+  endif()
+
   foreach(CURRENT_DEP_SPEC IN LISTS DEFINE_BACKEND_DEPENDENCIES)
     if (NOT "${CURRENT_DEP_SPEC}" MATCHES "^([a-zA-Z0-9_:-;]+) YIELDS ([a-zA-Z0-9_:-;]+)$")
       message(FATAL_ERROR "Invalid format for dependency specification in '${CURRENT_DEP_SPEC}'")
@@ -90,7 +95,6 @@ function(soci_define_backend_target)
         set(${DEFINE_BACKEND_ENABLED_VARIABLE} OFF CACHE STRING "${DESCRIPTION}" FORCE)
         return()
       elseif(BUILTIN_ON_MISSING_DEPENDENCY)
-        message(STATUS "Falling back on built-in version of '${CURRENT_DEP}' for SOCI backend '${DEFINE_BACKEND_NAME}'")
         break()
       else()
         message(FATAL_ERROR "Unspecified handling of unmet dependency")

docs/installation.md

@@ -92,6 +92,9 @@ When it comes to enabling specific backends, SOCI supports three distinct option
 * `OFF`: Disable the backend.
 * `ON`: Enables the backend. If one or more of its dependencies are unmet, error and abort configuration.
 
+SQLite backend is special, as it may use the built-in SQLite library if the system version is not found, see its documentation below for more details.
+
+
 #### Empty (sample backend)
 
 * `SOCI_EMPTY` - Enabler - Enables the [sample backend](backends/index.md) called Empty. Always ON by default.
@@ -146,7 +149,7 @@ Furthermore, the `MYSQL_DIR` _environment variable_ can be set to the MySQL inst
 
 #### SQLite 3
 
-* `SOCI_SQLITE3` - Enabler - Enables the [SQLite3](backends/sqlite3.md) backend. Note that, unlike with all the other backends, if SQLite3 library is not found, built-in version of SQLite3 is used instead of the backend being disabled.
+* `SOCI_SQLITE3` - Enabler - Enables the [SQLite3](backends/sqlite3.md) backend. Note that, unlike with all the other backends, if SQLite3 library is not found, built-in version of SQLite3 is used instead of the backend being disabled. `SOCI_SQLITE3_BUILTIN` can be set to `OFF` to prevent this from happening, i.e. force using system version only, or, on the contrary, set to `ON` to always use the built-in version, even if SQLite3 library is available on the system.
 * `SOCI_SQLITE3_TEST_CONNSTR` - string - Connection string is simply a file path where SQLite3 test database will be created (e.g. /home/john/soci_test.db). Check [SQLite3 backend reference](backends/sqlite3.md) for details. Example: `-DSOCI_SQLITE3_TEST_CONNSTR="my.db"` or `-DSOCI_SQLITE3_TEST_CONNSTR=":memory:"`.
 * `SOCI_SQLITE3_SKIP_TESTS` - boolean - Skips testing this backend.
 

src/backends/sqlite3/CMakeLists.txt

@@ -8,6 +8,10 @@ else()
   set(DEPENDENCY_MODE "ERROR")
 endif()
 
+# This variable is specific to this backend and allows to either force or
+# disable using the built-in copy of SQLite3.
+set(SOCI_SQLITE3_BUILTIN "" CACHE STRING "Prefer, or forbid, using the built-in SQLite3 library")
+
 soci_define_backend_target(
   NAME "SQLite3"
   TARGET_NAME "soci_sqlite3"
@@ -35,28 +39,37 @@ endif()
 
 # If SQLite3 was found, this target must have been created.
 if (NOT TARGET SQLite::SQLite3)
-  # But if it wasn't, use our built-in version, after checking that it is
-  # available.
-  if (NOT EXISTS "${PROJECT_SOURCE_DIR}/3rdparty/sqlite3/sqlite3.c")
-    message(WARNING "SQLite3 not found and built-in version not available, have you cloned SOCI repository with --recurse-submodules?")
+  set(SQLITE3_DIRECTORY "${PROJECT_SOURCE_DIR}/3rdparty/sqlite3")
+  set(SQLITE3_SOURCE_FILE "${SQLITE3_DIRECTORY}/sqlite3.c")
 
+  # But if it wasn't, use our built-in version, after checking that it is
+  # available, and if we're allowed to use it.
+  if (NOT "${SOCI_SQLITE3_BUILTIN}" STREQUAL "OFF")
+    if (NOT EXISTS ${SQLITE3_SOURCE_FILE})
+      message(WARNING "SQLite3 not found and built-in version not available, have you cloned SOCI repository with --recurse-submodules?")
+    else()
+      set(SOCI_SQLITE3_USE_BUILTIN ON)
+    endif()
+  endif()
+
+  if (NOT SOCI_SQLITE3_USE_BUILTIN)
     get_property(DESCRIPTION CACHE SOCI_SQLITE3 PROPERTY HELPSTRING)
     set(SOCI_SQLITE3 OFF CACHE STRING "${DESCRIPTION}" FORCE)
     return()
   endif()
 
-  add_library(soci_sqlite3_builtin)
-  target_sources(soci_sqlite3_builtin
-    PRIVATE
-      "${PROJECT_SOURCE_DIR}/3rdparty/sqlite3/sqlite3.c"
-  )
-  target_include_directories(soci_sqlite3_builtin
-    PUBLIC
-      "${PROJECT_SOURCE_DIR}/3rdparty/sqlite3"
-  )
+  if ("${SOCI_SQLITE3_BUILTIN}" STREQUAL "ON")
+    message(STATUS "Using built-in version of SQLite3")
+  else()
+    message(STATUS "Falling back on built-in version of SQLite3")
+  endif()
 
-  target_link_libraries(soci_sqlite3
+  target_sources(soci_sqlite3
     PRIVATE
-      soci_sqlite3_builtin
+      ${SQLITE3_SOURCE_FILE}
+  )
+  target_include_directories(soci_sqlite3
+    PRIVATE
+      ${SQLITE3_DIRECTORY}
   )
 endif()