compilers: Improve manual library searching

We can now specify the library type we want to search for, and whether
we want to prefer static libraries over shared ones or the other way
around. This functionality is not exposed to build files yet.

mesonbuild/build.py

@@ -22,7 +22,7 @@ from . import mlog
 from .mesonlib import File, MesonException, listify, extract_as_list
 from .mesonlib import typeslistify, stringlistify, classify_unity_sources
 from .mesonlib import get_filenames_templates_dict, substitute_values
-from .environment import for_windows, for_darwin, for_cygwin
+from .mesonlib import for_windows, for_darwin, for_cygwin
 from .compilers import is_object, clike_langs, sort_clike, lang_suffixes
 
 known_basic_kwargs = {'install': True,

mesonbuild/compilers/c.py

@@ -17,6 +17,7 @@ import subprocess, os.path, tempfile
 from .. import mlog
 from .. import coredata
 from ..mesonlib import EnvironmentException, version_compare, Popen_safe, listify
+from ..mesonlib import for_windows, for_darwin, for_cygwin
 
 from .compilers import (
     GCC_MINGW,
@@ -710,7 +711,45 @@ class CCompiler(Compiler):
                         return False
         raise RuntimeError('BUG: {!r} check failed unexpectedly'.format(n))
 
-    def find_library(self, libname, env, extra_dirs):
+    def get_library_naming(self, env, libtype):
+        '''
+        Get library prefixes and suffixes for the target platform ordered by
+        priority
+        '''
+        stlibext = ['a']
+        # We've always allowed libname to be both `foo` and `libfoo`,
+        # and now people depend on it
+        prefixes = ['lib', '']
+        # Library suffixes and prefixes
+        if for_darwin(env.is_cross_build(), env):
+            shlibext = ['dylib']
+        elif for_windows(env.is_cross_build(), env):
+            if self.id == 'msvc':
+                shlibext = ['lib']
+            else:
+                shlibext = ['dll', 'dll.a', 'lib']
+            # Yep, static libraries can also be foo.lib
+            stlibext += ['lib']
+        elif for_cygwin(env.is_cross_build(), env):
+            shlibext = ['dll', 'dll.a']
+            prefixes = ['cyg'] + prefixes
+        else:
+            # Linux/BSDs
+            shlibext = ['so']
+        # Search priority
+        if libtype in ('default', 'shared-static'):
+            suffixes = shlibext + stlibext
+        elif libtype == 'static-shared':
+            suffixes = stlibext + shlibext
+        elif libtype == 'shared':
+            suffixes = shlibext
+        elif libtype == 'static':
+            suffixes = stlibext
+        else:
+            raise AssertionError('BUG: unknown libtype {!r}'.format(libtype))
+        return prefixes, suffixes
+
+    def find_library(self, libname, env, extra_dirs, libtype='default'):
         # These libraries are either built-in or invalid
         if libname in self.ignore_libs:
             return []
@@ -720,21 +759,21 @@ class CCompiler(Compiler):
             extra_dirs = [extra_dirs]
         # Gcc + co seem to prefer builtin lib dirs to -L dirs.
         # Only try to find std libs if no extra dirs specified.
-        if not extra_dirs:
+        if not extra_dirs and libtype == 'default':
             args = ['-l' + libname]
             if self.links(code, env, extra_args=args):
                 return args
-        # Not found? Try to find the library file itself.
+        # Not found or we want to use a specific libtype? Try to find the
+        # library file itself.
         extra_dirs += self.get_library_dirs()
-        suffixes = ['so', 'dylib', 'lib', 'dll', 'a']
+        prefixes, suffixes = self.get_library_naming(env, libtype)
+        # Triply-nested loop!
         for d in extra_dirs:
             for suffix in suffixes:
-                trial = os.path.join(d, 'lib' + libname + '.' + suffix)
+                for prefix in prefixes:
-                if os.path.isfile(trial):
+                    trial = os.path.join(d, prefix + libname + '.' + suffix)
-                    return [trial]
+                    if os.path.isfile(trial):
-                trial2 = os.path.join(d, libname + '.' + suffix)
+                        return [trial]
-                if os.path.isfile(trial2):
-                    return [trial2]
         return None
 
     def thread_flags(self):

mesonbuild/dependencies/ui.py

@@ -23,8 +23,9 @@ from collections import OrderedDict
 
 from .. import mlog
 from .. import mesonlib
-from ..mesonlib import MesonException, Popen_safe, version_compare, extract_as_list
+from ..mesonlib import MesonException, Popen_safe, version_compare
-from ..environment import for_windows, detect_cpu
+from ..mesonlib import extract_as_list, for_windows
+from ..environment import detect_cpu
 
 from .base import DependencyException, DependencyMethods
 from .base import ExternalDependency, ExternalProgram

mesonbuild/environment.py

@@ -219,46 +219,6 @@ def detect_system():
         return 'cygwin'
     return system
 
-
-def for_windows(is_cross, env):
-    """
-    Host machine is windows?
-
-    Note: 'host' is the machine on which compiled binaries will run
-    """
-    if not is_cross:
-        return mesonlib.is_windows()
-    elif env.cross_info.has_host():
-        return env.cross_info.config['host_machine']['system'] == 'windows'
-    return False
-
-
-def for_cygwin(is_cross, env):
-    """
-    Host machine is cygwin?
-
-    Note: 'host' is the machine on which compiled binaries will run
-    """
-    if not is_cross:
-        return mesonlib.is_cygwin()
-    elif env.cross_info.has_host():
-        return env.cross_info.config['host_machine']['system'] == 'cygwin'
-    return False
-
-
-def for_darwin(is_cross, env):
-    """
-    Host machine is Darwin (iOS/OS X)?
-
-    Note: 'host' is the machine on which compiled binaries will run
-    """
-    if not is_cross:
-        return mesonlib.is_osx()
-    elif env.cross_info.has_host():
-        return env.cross_info.config['host_machine']['system'] == 'darwin'
-    return False
-
-
 def search_version(text):
     # Usually of the type 4.1.4 but compiler output may contain
     # stuff like this:
@@ -550,9 +510,9 @@ class Environment:
                 cls = GnuCCompiler if lang == 'c' else GnuCPPCompiler
                 return cls(ccache + compiler, version, gtype, is_cross, exe_wrap, defines)
             if 'clang' in out:
-                if 'Apple' in out or for_darwin(want_cross, self):
+                if 'Apple' in out or mesonlib.for_darwin(want_cross, self):
                     cltype = CLANG_OSX
-                elif 'windows' in out or for_windows(want_cross, self):
+                elif 'windows' in out or mesonlib.for_windows(want_cross, self):
                     cltype = CLANG_WIN
                 else:
                     cltype = CLANG_STANDARD

mesonbuild/mesonlib.py

@@ -219,6 +219,42 @@ def is_cygwin():
 def is_debianlike():
     return os.path.isfile('/etc/debian_version')
 
+def for_windows(is_cross, env):
+    """
+    Host machine is windows?
+
+    Note: 'host' is the machine on which compiled binaries will run
+    """
+    if not is_cross:
+        return is_windows()
+    elif env.cross_info.has_host():
+        return env.cross_info.config['host_machine']['system'] == 'windows'
+    return False
+
+def for_cygwin(is_cross, env):
+    """
+    Host machine is cygwin?
+
+    Note: 'host' is the machine on which compiled binaries will run
+    """
+    if not is_cross:
+        return is_cygwin()
+    elif env.cross_info.has_host():
+        return env.cross_info.config['host_machine']['system'] == 'cygwin'
+    return False
+
+def for_darwin(is_cross, env):
+    """
+    Host machine is Darwin (iOS/OS X)?
+
+    Note: 'host' is the machine on which compiled binaries will run
+    """
+    if not is_cross:
+        return is_osx()
+    elif env.cross_info.has_host():
+        return env.cross_info.config['host_machine']['system'] == 'darwin'
+    return False
+
 def exe_exists(arglist):
     try:
         p = subprocess.Popen(arglist, stdout=subprocess.PIPE, stderr=subprocess.PIPE)