Use an optional for ConfigValueStr

9 files changed, 86 insertions, 85 deletions

diff --git a/Alc/alc.cpp b/Alc/alc.cpp
index ec9953fe..7cf28ed3 100644
--- a/Alc/alc.cpp
+++ b/Alc/alc.cpp
@@ -1024,8 +1024,9 @@ void alc_initconfig(void)
 #ifdef HAVE_NEON
     capfilter |= CPU_CAP_NEON;
 #endif
-    if(ConfigValueStr(nullptr, nullptr, "disable-cpu-exts", &str))
+    if(auto cpuopt = ConfigValueStr(nullptr, nullptr, "disable-cpu-exts"))
     {
+        str = cpuopt->c_str();
         if(strcasecmp(str, "all") == 0)
             capfilter = 0;
         else
@@ -1094,15 +1095,20 @@ void alc_initconfig(void)
     if(ConfigValueFloat(nullptr, "reverb", "boost", &valf))
         ReverbBoost *= std::pow(10.0f, valf / 20.0f);
 
-    const char *devs{getenv("ALSOFT_DRIVERS")};
-    if((devs && devs[0]) || ConfigValueStr(nullptr, nullptr, "drivers", &devs))
+    auto devopt = ConfigValueStr(nullptr, nullptr, "drivers");
+    if(const char *devs{getenv("ALSOFT_DRIVERS")})
+    {
+        if(devs[0])
+            devopt = al::optional<std::string>{al::in_place, devs};
+    }
+    if(devopt)
     {
         auto backendlist_cur = std::begin(BackendList);
 
         bool endlist{true};
-        const char *next = devs;
+        const char *next{devopt->c_str()};
         do {
-            devs = next;
+            const char *devs{next};
             while(isspace(devs[0]))
                 devs++;
             next = strchr(devs, ',');
@@ -1182,9 +1188,9 @@ void alc_initconfig(void)
     if(!CaptureFactory)
         WARN("No capture backend available!\n");
 
-    if(ConfigValueStr(nullptr, nullptr, "excludefx", &str))
+    if(auto exclopt = ConfigValueStr(nullptr, nullptr, "excludefx"))
     {
-        const char *next = str;
+        const char *next{exclopt->c_str()};
         do {
             str = next;
             next = strchr(str, ',');
@@ -1203,9 +1209,10 @@ void alc_initconfig(void)
     }
 
     InitEffect(&DefaultEffect);
-    str = getenv("ALSOFT_DEFAULT_REVERB");
-    if((str && str[0]) || ConfigValueStr(nullptr, nullptr, "default-reverb", &str))
-        LoadReverbPreset(str, &DefaultEffect);
+    auto defrevopt = ConfigValueStr(nullptr, nullptr, "default-reverb");
+    if((str=getenv("ALSOFT_DEFAULT_REVERB")) && str[0])
+        defrevopt = al::optional<std::string>{al::in_place, str};
+    if(defrevopt) LoadReverbPreset(defrevopt->c_str(), &DefaultEffect);
 }
 #define DO_INITCONFIG() std::call_once(alc_config_once, [](){alc_initconfig();})
 
@@ -1919,9 +1926,9 @@ static ALCenum UpdateDeviceParams(ALCdevice *device, const ALCint *attrList)
     device->HrtfStatus = ALC_HRTF_DISABLED_SOFT;
     if(device->Type != Loopback)
     {
-        const char *hrtf;
-        if(ConfigValueStr(device->DeviceName.c_str(), nullptr, "hrtf", &hrtf))
+        if(auto hrtfopt = ConfigValueStr(device->DeviceName.c_str(), nullptr, "hrtf"))
         {
+            const char *hrtf{hrtfopt->c_str()};
             if(strcasecmp(hrtf, "true") == 0)
                 hrtf_userreq = Hrtf_Enable;
             else if(strcasecmp(hrtf, "false") == 0)
@@ -3743,8 +3750,7 @@ START_API_FUNC
     }
 
     deviceName = device->DeviceName.c_str();
-    const ALCchar *fmt{};
-    if(ConfigValueStr(deviceName, nullptr, "channels", &fmt))
+    if(auto chanopt = ConfigValueStr(deviceName, nullptr, "channels"))
     {
         static constexpr struct ChannelMap {
             const char name[16];
@@ -3763,6 +3769,7 @@ START_API_FUNC
             { "ambi3", DevFmtAmbi3D, 3 },
         };
 
+        const ALCchar *fmt{chanopt->c_str()};
         auto iter = std::find_if(std::begin(chanlist), std::end(chanlist),
             [fmt](const ChannelMap &entry) -> bool
             { return strcasecmp(entry.name, fmt) == 0; }
@@ -3776,7 +3783,7 @@ START_API_FUNC
             device->Flags.set<ChannelsRequest>();
         }
     }
-    if(ConfigValueStr(deviceName, nullptr, "sample-type", &fmt))
+    if(auto typeopt = ConfigValueStr(deviceName, nullptr, "sample-type"))
     {
         static constexpr struct TypeMap {
             const char name[16];
@@ -3791,6 +3798,7 @@ START_API_FUNC
             { "float32", DevFmtFloat  },
         };
 
+        const ALCchar *fmt{typeopt->c_str()};
         auto iter = std::find_if(std::begin(typelist), std::end(typelist),
             [fmt](const TypeMap &entry) -> bool
             { return strcasecmp(entry.name, fmt) == 0; }
@@ -3842,8 +3850,9 @@ START_API_FUNC
     device->NumStereoSources = 1;
     device->NumMonoSources = device->SourcesMax - device->NumStereoSources;
 
-    if(ConfigValueStr(deviceName, nullptr, "ambi-format", &fmt))
+    if(auto ambiopt = ConfigValueStr(deviceName, nullptr, "ambi-format"))
     {
+        const ALCchar *fmt{ambiopt->c_str()};
         if(strcasecmp(fmt, "fuma") == 0)
         {
             if(device->mAmbiOrder > 3)
diff --git a/Alc/alconfig.cpp b/Alc/alconfig.cpp
index 8b299afc..c5abd6ab 100644
--- a/Alc/alconfig.cpp
+++ b/Alc/alconfig.cpp
@@ -492,13 +492,12 @@ int ConfigValueExists(const char *devName, const char *blockName, const char *ke
     return val[0] != 0;
 }
 
-int ConfigValueStr(const char *devName, const char *blockName, const char *keyName, const char **ret)
+al::optional<std::string> ConfigValueStr(const char *devName, const char *blockName, const char *keyName)
 {
     const char *val = GetConfigValue(devName, blockName, keyName, "");
-    if(!val[0]) return 0;
+    if(!val[0]) return al::nullopt;
 
-    *ret = val;
-    return 1;
+    return al::optional<std::string>{al::in_place, val};
 }
 
 al::optional<int> ConfigValueInt(const char *devName, const char *blockName, const char *keyName)
diff --git a/Alc/alconfig.h b/Alc/alconfig.h
index 275fed75..9b1c09aa 100644
--- a/Alc/alconfig.h
+++ b/Alc/alconfig.h
@@ -1,6 +1,8 @@
 #ifndef ALCONFIG_H
 #define ALCONFIG_H
 
+#include <string>
+
 #include "aloptional.h"
 
 void ReadALConfig();
@@ -9,7 +11,7 @@ int ConfigValueExists(const char *devName, const char *blockName, const char *ke
 const char *GetConfigValue(const char *devName, const char *blockName, const char *keyName, const char *def);
 int GetConfigValueBool(const char *devName, const char *blockName, const char *keyName, int def);
 
-int ConfigValueStr(const char *devName, const char *blockName, const char *keyName, const char **ret);
+al::optional<std::string> ConfigValueStr(const char *devName, const char *blockName, const char *keyName);
 al::optional<int> ConfigValueInt(const char *devName, const char *blockName, const char *keyName);
 al::optional<unsigned int> ConfigValueUInt(const char *devName, const char *blockName, const char *keyName);
 int ConfigValueFloat(const char *devName, const char *blockName, const char *keyName, float *ret);
diff --git a/Alc/backends/alsa.cpp b/Alc/backends/alsa.cpp
index ebdc6129..aeb38585 100644
--- a/Alc/backends/alsa.cpp
+++ b/Alc/backends/alsa.cpp
@@ -207,11 +207,6 @@ ALSA_FUNCS(MAKE_FUNC);
 struct DevMap {
     std::string name;
     std::string device_name;
-
-    template<typename StrT0, typename StrT1>
-    DevMap(StrT0&& name_, StrT1&& devname_)
-      : name{std::forward<StrT0>(name_)}, device_name{std::forward<StrT1>(devname_)}
-    { }
 };
 
 al::vector<DevMap> PlaybackDevices;
@@ -233,10 +228,9 @@ al::vector<DevMap> probe_devices(snd_pcm_stream_t stream)
     snd_pcm_info_t *pcminfo;
     snd_pcm_info_malloc(&pcminfo);
 
-    devlist.emplace_back(alsaDevice,
+    devlist.emplace_back(DevMap{alsaDevice,
         GetConfigValue(nullptr, "alsa", (stream==SND_PCM_STREAM_PLAYBACK) ? "device" : "capture",
-            "default")
-    );
+            "default")});
 
     if(stream == SND_PCM_STREAM_PLAYBACK)
     {
@@ -254,15 +248,15 @@ al::vector<DevMap> probe_devices(snd_pcm_stream_t stream)
             }
 
             const char *oldsep{sep++};
-            devlist.emplace_back(std::string(customdevs, oldsep),
-                next ? std::string(sep, next++) : std::string(sep));
+            devlist.emplace_back(DevMap{std::string(customdevs, oldsep),
+                next ? std::string(sep, next++) : std::string(sep)});
             const auto &entry = devlist.back();
             TRACE("Got device \"%s\", \"%s\"\n", entry.name.c_str(), entry.device_name.c_str());
         }
     }
 
-    const char *main_prefix{"plughw:"};
-    ConfigValueStr(nullptr, "alsa", prefix_name(stream), &main_prefix);
+    const std::string main_prefix{
+        ConfigValueStr(nullptr, "alsa", prefix_name(stream)).value_or("plughw:")};
 
     int card{-1};
     int err{snd_card_next(&card)};
@@ -288,9 +282,8 @@ al::vector<DevMap> probe_devices(snd_pcm_stream_t stream)
         name = prefix_name(stream);
         name += '-';
         name += cardid;
-
-        const char *card_prefix{main_prefix};
-        ConfigValueStr(nullptr, "alsa", name.c_str(), &card_prefix);
+        const std::string card_prefix{
+            ConfigValueStr(nullptr, "alsa", name.c_str()).value_or(main_prefix)};
 
         int dev{-1};
         while(1)
@@ -315,8 +308,8 @@ al::vector<DevMap> probe_devices(snd_pcm_stream_t stream)
             name += cardid;
             name += '-';
             name += std::to_string(dev);
-            const char *device_prefix{card_prefix};
-            ConfigValueStr(nullptr, "alsa", name.c_str(), &device_prefix);
+            const std::string device_prefix{
+                ConfigValueStr(nullptr, "alsa", name.c_str()).value_or(card_prefix)};
 
             /* "CardName, PcmName (CARD=cardid,DEV=dev)" */
             name = cardname;
@@ -335,7 +328,7 @@ al::vector<DevMap> probe_devices(snd_pcm_stream_t stream)
             device += ",DEV=";
             device += std::to_string(dev);
             
-            devlist.emplace_back(std::move(name), std::move(device));
+            devlist.emplace_back(DevMap{std::move(name), std::move(device)});
             const auto &entry = devlist.back();
             TRACE("Got device \"%s\", \"%s\"\n", entry.name.c_str(), entry.device_name.c_str());
         }
diff --git a/Alc/backends/oss.cpp b/Alc/backends/oss.cpp
index 0a28fcd8..e5b74334 100644
--- a/Alc/backends/oss.cpp
+++ b/Alc/backends/oss.cpp
@@ -80,17 +80,12 @@
 namespace {
 
 constexpr char DefaultName[] = "OSS Default";
-const char *DefaultPlayback{"/dev/dsp"};
-const char *DefaultCapture{"/dev/dsp"};
+std::string DefaultPlayback{"/dev/dsp"};
+std::string DefaultCapture{"/dev/dsp"};
 
 struct DevMap {
     std::string name;
     std::string device_name;
-
-    template<typename StrT0, typename StrT1>
-    DevMap(StrT0&& name_, StrT1&& devname_)
-      : name{std::forward<StrT0>(name_)}, device_name{std::forward<StrT1>(devname_)}
-    { }
 };
 
 bool checkName(const al::vector<DevMap> &list, const std::string &name)
@@ -111,7 +106,7 @@ al::vector<DevMap> CaptureDevices;
 #define DSP_CAP_INPUT 0x00010000
 void ALCossListPopulate(al::vector<DevMap> *devlist, int type)
 {
-    devlist->emplace_back(DefaultName, (type==DSP_CAP_INPUT) ? DefaultCapture : DefaultPlayback);
+    devlist->emplace_back(DevMap{DefaultName, (type==DSP_CAP_INPUT) ? DefaultCapture : DefaultPlayback});
 }
 
 #else
@@ -156,7 +151,7 @@ void ALCossListAppend(al::vector<DevMap> *list, const char *handle, size_t hlen,
         newname += std::to_string(++count);
     }
 
-    list->emplace_back(std::move(newname), std::move(devname));
+    list->emplace_back(DevMap{std::move(newname), std::move(devname)});
     const DevMap &entry = list->back();
 
     TRACE("Got device \"%s\", \"%s\"\n", entry.name.c_str(), entry.device_name.c_str());
@@ -212,7 +207,7 @@ done:
         close(fd);
     fd = -1;
 
-    const char *defdev{(type_flag==DSP_CAP_INPUT) ? DefaultCapture : DefaultPlayback};
+    const char *defdev{((type_flag==DSP_CAP_INPUT) ? DefaultCapture : DefaultPlayback).c_str()};
     auto iter = std::find_if(devlist->cbegin(), devlist->cend(),
         [defdev](const DevMap &entry) -> bool
         { return entry.device_name == defdev; }
@@ -331,7 +326,7 @@ int OSSPlayback::mixerProc()
 
 ALCenum OSSPlayback::open(const ALCchar *name)
 {
-    const char *devname{DefaultPlayback};
+    const char *devname{DefaultPlayback.c_str()};
     if(!name)
         name = DefaultName;
     else
@@ -548,7 +543,7 @@ int OSScapture::recordProc()
 
 ALCenum OSScapture::open(const ALCchar *name)
 {
-    const char *devname{DefaultCapture};
+    const char *devname{DefaultCapture.c_str()};
     if(!name)
         name = DefaultName;
     else
@@ -700,8 +695,10 @@ BackendFactory &OSSBackendFactory::getFactory()
 
 bool OSSBackendFactory::init()
 {
-    ConfigValueStr(nullptr, "oss", "device", &DefaultPlayback);
-    ConfigValueStr(nullptr, "oss", "capture", &DefaultCapture);
+    if(auto devopt = ConfigValueStr(nullptr, "oss", "device"))
+        DefaultPlayback = std::move(*devopt);
+    if(auto capopt = ConfigValueStr(nullptr, "oss", "capture"))
+        DefaultCapture = std::move(*capopt);
 
     return true;
 }
diff --git a/Alc/backends/solaris.cpp b/Alc/backends/solaris.cpp
index 5c378bff..5c12ad72 100644
--- a/Alc/backends/solaris.cpp
+++ b/Alc/backends/solaris.cpp
@@ -52,7 +52,7 @@ namespace {
 
 constexpr ALCchar solaris_device[] = "Solaris Default";
 
-const char *solaris_driver = "/dev/audio";
+std::string solaris_driver{"/dev/audio"};
 
 
 struct SolarisBackend final : public BackendBase {
@@ -149,10 +149,10 @@ ALCenum SolarisBackend::open(const ALCchar *name)
     else if(strcmp(name, solaris_device) != 0)
         return ALC_INVALID_VALUE;
 
-    mFd = ::open(solaris_driver, O_WRONLY);
+    mFd = ::open(solaris_driver.c_str(), O_WRONLY);
     if(mFd == -1)
     {
-        ERR("Could not open %s: %s\n", solaris_driver, strerror(errno));
+        ERR("Could not open %s: %s\n", solaris_driver.c_str(), strerror(errno));
         return ALC_INVALID_VALUE;
     }
 
@@ -267,7 +267,8 @@ BackendFactory &SolarisBackendFactory::getFactory()
 
 bool SolarisBackendFactory::init()
 {
-    ConfigValueStr(nullptr, "solaris", "device", &solaris_driver);
+    if(auto devopt = ConfigValueStr(nullptr, "solaris", "device"))
+        solaris_driver = std::move(*devopt);
     return true;
 }
 
@@ -282,7 +283,7 @@ void SolarisBackendFactory::probe(DevProbe type, std::string *outnames)
         {
 #ifdef HAVE_STAT
             struct stat buf;
-            if(stat(solaris_driver, &buf) == 0)
+            if(stat(solaris_driver.c_str(), &buf) == 0)
 #endif
                 outnames->append(solaris_device, sizeof(solaris_device));
         }
diff --git a/Alc/hrtf.cpp b/Alc/hrtf.cpp
index 6b3edd9f..d86c4ecf 100644
--- a/Alc/hrtf.cpp
+++ b/Alc/hrtf.cpp
@@ -1214,9 +1214,9 @@ al::vector<EnumeratedHrtf> EnumerateHrtf(const char *devname)
     al::vector<EnumeratedHrtf> list;
 
     bool usedefaults{true};
-    const char *pathlist{""};
-    if(ConfigValueStr(devname, nullptr, "hrtf-paths", &pathlist))
+    if(auto pathopt = ConfigValueStr(devname, nullptr, "hrtf-paths"))
     {
+        const char *pathlist{pathopt->c_str()};
         while(pathlist && *pathlist)
         {
             const char *next, *end;
@@ -1262,20 +1262,22 @@ al::vector<EnumeratedHrtf> EnumerateHrtf(const char *devname)
             AddBuiltInEntry(list, "Built-In 48000hz", IDR_DEFAULT_48000_MHR);
     }
 
-    const char *defaulthrtf{""};
-    if(!list.empty() && ConfigValueStr(devname, nullptr, "default-hrtf", &defaulthrtf))
+    if(!list.empty())
     {
-        auto iter = std::find_if(list.begin(), list.end(),
-            [defaulthrtf](const EnumeratedHrtf &entry) -> bool
-            { return entry.name == defaulthrtf; }
-        );
-        if(iter == list.end())
-            WARN("Failed to find default HRTF \"%s\"\n", defaulthrtf);
-        else if(iter != list.begin())
+        if(auto defhrtfopt = ConfigValueStr(devname, nullptr, "default-hrtf"))
         {
-            EnumeratedHrtf entry{*iter};
-            list.erase(iter);
-            list.insert(list.begin(), entry);
+            auto iter = std::find_if(list.begin(), list.end(),
+                [&defhrtfopt](const EnumeratedHrtf &entry) -> bool
+                { return entry.name == *defhrtfopt; }
+            );
+            if(iter == list.end())
+                WARN("Failed to find default HRTF \"%s\"\n", defhrtfopt->c_str());
+            else if(iter != list.begin())
+            {
+                EnumeratedHrtf entry{std::move(*iter)};
+                list.erase(iter);
+                list.insert(list.begin(), std::move(entry));
+            }
         }
     }
 
diff --git a/Alc/mixvoice.cpp b/Alc/mixvoice.cpp
index 9408d096..9b0196d9 100644
--- a/Alc/mixvoice.cpp
+++ b/Alc/mixvoice.cpp
@@ -155,10 +155,9 @@ ResamplerFunc SelectResampler(Resampler resampler)
 
 void aluInitMixer()
 {
-    const char *str;
-
-    if(ConfigValueStr(nullptr, nullptr, "resampler", &str))
+    if(auto resopt = ConfigValueStr(nullptr, nullptr, "resampler"))
     {
+        const char *str{resopt->c_str()};
         if(strcasecmp(str, "point") == 0 || strcasecmp(str, "none") == 0)
             ResamplerDefault = PointResampler;
         else if(strcasecmp(str, "linear") == 0)
diff --git a/Alc/panning.cpp b/Alc/panning.cpp
index 864d7f28..aa290821 100644
--- a/Alc/panning.cpp
+++ b/Alc/panning.cpp
@@ -553,9 +553,9 @@ void InitHrtfPanning(ALCdevice *device)
      */
     device->mRenderMode = HrtfRender;
     ALsizei ambi_order{1};
-    const char *mode;
-    if(ConfigValueStr(device->DeviceName.c_str(), nullptr, "hrtf-mode", &mode))
+    if(auto modeopt = ConfigValueStr(device->DeviceName.c_str(), nullptr, "hrtf-mode"))
     {
+        const char *mode{modeopt->c_str()};
         if(strcasecmp(mode, "basic") == 0)
         {
             ERR("HRTF mode \"%s\" deprecated, substituting \"%s\"\n", mode, "ambi2");
@@ -783,11 +783,10 @@ void aluInitRenderer(ALCdevice *device, ALint hrtf_id, HrtfRequestMode hrtf_appr
         AmbDecConf conf{};
         if(layout)
         {
-            const char *fname;
-            if(ConfigValueStr(devname, "decoder", layout, &fname))
+            if(auto decopt = ConfigValueStr(devname, "decoder", layout))
             {
-                if(!conf.load(fname))
-                    ERR("Failed to load layout file %s\n", fname);
+                if(!conf.load(decopt->c_str()))
+                    ERR("Failed to load layout file %s\n", decopt->c_str());
                 else if(conf.Speakers.size() > MAX_OUTPUT_CHANNELS)
                     ERR("Unsupported speaker count %zu (max %d)\n", conf.Speakers.size(),
                         MAX_OUTPUT_CHANNELS);
@@ -814,9 +813,9 @@ void aluInitRenderer(ALCdevice *device, ALint hrtf_id, HrtfRequestMode hrtf_appr
     bool headphones{device->IsHeadphones != AL_FALSE};
     if(device->Type != Loopback)
     {
-        const char *mode;
-        if(ConfigValueStr(device->DeviceName.c_str(), nullptr, "stereo-mode", &mode))
+        if(auto modeopt = ConfigValueStr(device->DeviceName.c_str(), nullptr, "stereo-mode"))
         {
+            const char *mode{modeopt->c_str()};
             if(strcasecmp(mode, "headphones") == 0)
                 headphones = true;
             else if(strcasecmp(mode, "speakers") == 0)
@@ -916,9 +915,9 @@ no_hrtf:
         }
     }
 
-    const char *mode;
-    if(ConfigValueStr(device->DeviceName.c_str(), nullptr, "stereo-encoding", &mode))
+    if(auto encopt = ConfigValueStr(device->DeviceName.c_str(), nullptr, "stereo-encoding"))
     {
+        const char *mode{encopt->c_str()};
         if(strcasecmp(mode, "uhj") == 0)
             device->mRenderMode = NormalRender;
         else if(strcasecmp(mode, "panpot") != 0)