Add methods to get env vars as an optional

9 files changed, 137 insertions, 94 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6ce57dc3..c11d311c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -604,6 +604,7 @@ SET(COMMON_OBJS
     common/intrusive_ptr.h
     common/math_defs.h
     common/opthelpers.h
+    common/strutils.cpp
     common/strutils.h
     common/threads.cpp
     common/threads.h
diff --git a/al/state.cpp b/al/state.cpp
index 8c95c22f..884aa9d2 100644
--- a/al/state.cpp
+++ b/al/state.cpp
@@ -42,6 +42,7 @@
 #include "event.h"
 #include "inprogext.h"
 #include "opthelpers.h"
+#include "strutils.h"
 
 
 namespace {
@@ -73,8 +74,8 @@ constexpr ALchar alBSinc24Resampler[] = "23rd order Sinc";
 extern "C" AL_API const ALchar* AL_APIENTRY alsoft_get_version(void)
 START_API_FUNC
 {
-    const char *spoof{getenv("ALSOFT_SPOOF_VERSION")};
-    if(spoof && spoof[0] != '\0') return spoof;
+    static const auto spoof = al::getenv("ALSOFT_SPOOF_VERSION");
+    if(spoof) return spoof->c_str();
     return ALSOFT_VERSION;
 }
 END_API_FUNC
diff --git a/alc/alc.cpp b/alc/alc.cpp
index adead648..d4cf040a 100644
--- a/alc/alc.cpp
+++ b/alc/alc.cpp
@@ -929,25 +929,23 @@ std::recursive_mutex ListLock;
 
 void alc_initconfig(void)
 {
-    const char *str{getenv("ALSOFT_LOGLEVEL")};
-    if(str)
+    if(auto loglevel = al::getenv("ALSOFT_LOGLEVEL"))
     {
-        long lvl = strtol(str, nullptr, 0);
+        long lvl = strtol(loglevel->c_str(), nullptr, 0);
         if(lvl >= NoLog && lvl <= LogRef)
             gLogLevel = static_cast<LogLevel>(lvl);
     }
 
-    str = getenv("ALSOFT_LOGFILE");
-    if(str && str[0])
+    if(auto logfile = al::getenv("ALSOFT_LOGFILE"))
     {
 #ifdef _WIN32
-        std::wstring wname{utf8_to_wstr(str)};
-        FILE *logfile = _wfopen(wname.c_str(), L"wt");
+        std::wstring wname{utf8_to_wstr(logfile->c_str())};
+        FILE *logf{_wfopen(wname.c_str(), L"wt")};
 #else
-        FILE *logfile = fopen(str, "wt");
+        FILE *logf{fopen(logfile->c_str(), "wt")};
 #endif
-        if(logfile) gLogFile = logfile;
-        else ERR("Failed to open log file '%s'\n", str);
+        if(logf) gLogFile = logf;
+        else ERR("Failed to open log file '%s'\n", logfile->c_str());
     }
 
     TRACE("Initializing library v%s-%s %s\n", ALSOFT_VERSION, ALSOFT_GIT_COMMIT_HASH,
@@ -970,16 +968,15 @@ void alc_initconfig(void)
     }
     ReadALConfig();
 
-    str = getenv("__ALSOFT_SUSPEND_CONTEXT");
-    if(str && *str)
+    if(auto suspendmode = al::getenv("__ALSOFT_SUSPEND_CONTEXT"))
     {
-        if(strcasecmp(str, "ignore") == 0)
+        if(strcasecmp(suspendmode->c_str(), "ignore") == 0)
         {
             SuspendDefers = false;
             TRACE("Selected context suspend behavior, \"ignore\"\n");
         }
         else
-            ERR("Unhandled context suspend behavior setting: \"%s\"\n", str);
+            ERR("Unhandled context suspend behavior setting: \"%s\"\n", suspendmode->c_str());
     }
 
     int capfilter{0};
@@ -997,7 +994,7 @@ void alc_initconfig(void)
 #endif
     if(auto cpuopt = ConfigValueStr(nullptr, nullptr, "disable-cpu-exts"))
     {
-        str = cpuopt->c_str();
+        const char *str{cpuopt->c_str()};
         if(strcasecmp(str, "all") == 0)
             capfilter = 0;
         else
@@ -1043,22 +1040,31 @@ void alc_initconfig(void)
     aluInit();
     aluInitMixer();
 
-    str = getenv("ALSOFT_TRAP_ERROR");
-    if(str && (strcasecmp(str, "true") == 0 || strtol(str, nullptr, 0) == 1))
+    auto traperr = al::getenv("ALSOFT_TRAP_ERROR");
+    if(traperr && (strcasecmp(traperr->c_str(), "true") == 0
+            || strtol(traperr->c_str(), nullptr, 0) == 1))
     {
         TrapALError  = true;
         TrapALCError = true;
     }
     else
     {
-        str = getenv("ALSOFT_TRAP_AL_ERROR");
-        if(str && (strcasecmp(str, "true") == 0 || strtol(str, nullptr, 0) == 1))
-            TrapALError = true;
+        traperr = al::getenv("ALSOFT_TRAP_AL_ERROR");
+        if(traperr)
+        {
+            if(strcasecmp(traperr->c_str(), "true") == 0
+                || strtol(traperr->c_str(), nullptr, 0) == 1)
+                TrapALError = true;
+        }
         TrapALError = !!GetConfigValueBool(nullptr, nullptr, "trap-al-error", TrapALError);
 
-        str = getenv("ALSOFT_TRAP_ALC_ERROR");
-        if(str && (strcasecmp(str, "true") == 0 || strtol(str, nullptr, 0) == 1))
+        traperr = al::getenv("ALSOFT_TRAP_ALC_ERROR");
+        if(traperr)
+        {
+            if(strcasecmp(traperr->c_str(), "true") == 0
+                || strtol(traperr->c_str(), nullptr, 0) == 1)
             TrapALCError = true;
+        }
         TrapALCError = !!GetConfigValueBool(nullptr, nullptr, "trap-alc-error", TrapALCError);
     }
 
@@ -1068,13 +1074,8 @@ void alc_initconfig(void)
         ReverbBoost *= std::pow(10.0f, valf / 20.0f);
     }
 
-    auto devopt = ConfigValueStr(nullptr, nullptr, "drivers");
-    if(const char *devs{getenv("ALSOFT_DRIVERS")})
-    {
-        if(devs[0])
-            devopt = devs;
-    }
-    if(devopt)
+    auto devopt = al::getenv("ALSOFT_DRIVERS");
+    if(devopt || (devopt=ConfigValueStr(nullptr, nullptr, "drivers")))
     {
         auto backendlist_cur = std::begin(BackendList);
 
@@ -1165,7 +1166,7 @@ void alc_initconfig(void)
     {
         const char *next{exclopt->c_str()};
         do {
-            str = next;
+            const char *str{next};
             next = strchr(str, ',');
 
             if(!str[0] || next == str)
@@ -1182,10 +1183,9 @@ void alc_initconfig(void)
     }
 
     InitEffect(&DefaultEffect);
-    auto defrevopt = ConfigValueStr(nullptr, nullptr, "default-reverb");
-    if((str=getenv("ALSOFT_DEFAULT_REVERB")) && str[0])
-        defrevopt = str;
-    if(defrevopt) LoadReverbPreset(defrevopt->c_str(), &DefaultEffect);
+    auto defrevopt = al::getenv("ALSOFT_DEFAULT_REVERB");
+    if(defrevopt || (defrevopt=ConfigValueStr(nullptr, nullptr, "default-reverb")))
+        LoadReverbPreset(defrevopt->c_str(), &DefaultEffect);
 }
 #define DO_INITCONFIG() std::call_once(alc_config_once, [](){alc_initconfig();})
 
diff --git a/alc/alconfig.cpp b/alc/alconfig.cpp
index f6190b58..93c37703 100644
--- a/alc/alconfig.cpp
+++ b/alc/alconfig.cpp
@@ -81,6 +81,7 @@ std::string expdup(const char *str)
 {
     std::string output;
 
+    std::string envval;
     while(*str != '\0')
     {
         const char *addstr;
@@ -107,20 +108,20 @@ std::string expdup(const char *str)
             }
             else
             {
-                bool hasbraces{(*str == '{')};
-                if(hasbraces) str++;
-
-                std::string envname;
-                while((std::isalnum(*str) || *str == '_'))
-                    envname += *(str++);
+                const bool hasbraces{(*str == '{')};
 
+                if(hasbraces) str++;
+                const char *envstart = str;
+                while(std::isalnum(*str) || *str == '_')
+                    ++str;
                 if(hasbraces && *str != '}')
                     continue;
-
+                const std::string envname{envstart, str};
                 if(hasbraces) str++;
-                if((addstr=std::getenv(envname.c_str())) == nullptr)
-                    continue;
-                addstrlen = std::strlen(addstr);
+
+                envval = al::getenv(envname.c_str()).value_or(std::string{});
+                addstr = envval.data();
+                addstrlen = envval.length();
             }
         }
         if(addstrlen == 0)
@@ -308,18 +309,17 @@ void ReadALConfig()
             LoadConfigFromFile(f);
     }
 
-    const WCHAR *str{_wgetenv(L"ALSOFT_CONF")};
-    if(str != nullptr && *str)
+    if(auto confpath = al::getenv(L"ALSOFT_CONF"))
     {
-        std::string filepath{wstr_to_utf8(str)};
-
-        TRACE("Loading config %s...\n", filepath.c_str());
-        al::ifstream f{filepath};
+        TRACE("Loading config %s...\n", wstr_to_utf8(confpath->c_str()).c_str());
+        al::ifstream f{*confpath};
         if(f.is_open())
             LoadConfigFromFile(f);
     }
 }
+
 #else
+
 void ReadALConfig()
 {
     const char *str{"/etc/openal/alsoft.conf"};
@@ -330,9 +330,7 @@ void ReadALConfig()
         LoadConfigFromFile(f);
     f.close();
 
-    if(!(str=getenv("XDG_CONFIG_DIRS")) || str[0] == 0)
-        str = "/etc/xdg";
-    std::string confpaths = str;
+    std::string confpaths{al::getenv("XDG_CONFIG_DIRS").value_or("/etc/xdg")};
     /* Go through the list in reverse, since "the order of base directories
      * denotes their importance; the first directory listed is the most
      * important". Ergo, we need to load the settings from the later dirs
@@ -385,9 +383,9 @@ void ReadALConfig()
     }
 #endif
 
-    if((str=getenv("HOME")) != nullptr && *str)
+    if(auto homedir = al::getenv("HOME"))
     {
-        fname = str;
+        fname = *homedir;
         if(fname.back() != '/') fname += "/.alsoftrc";
         else fname += ".alsoftrc";
 
@@ -397,18 +395,18 @@ void ReadALConfig()
             LoadConfigFromFile(f);
     }
 
-    if((str=getenv("XDG_CONFIG_HOME")) != nullptr && str[0] != 0)
+    if(auto configdir = al::getenv("XDG_CONFIG_HOME"))
     {
-        fname = str;
+        fname = *configdir;
         if(fname.back() != '/') fname += "/alsoft.conf";
         else fname += "alsoft.conf";
     }
     else
     {
         fname.clear();
-        if((str=getenv("HOME")) != nullptr && str[0] != 0)
+        if(auto homedir = al::getenv("HOME"))
         {
-            fname = str;
+            fname = *homedir;
             if(fname.back() != '/') fname += "/.config/alsoft.conf";
             else fname += ".config/alsoft.conf";
         }
@@ -433,10 +431,10 @@ void ReadALConfig()
             LoadConfigFromFile(f);
     }
 
-    if((str=getenv("ALSOFT_CONF")) != nullptr && *str)
+    if(auto confname = al::getenv("ALSOFT_CONF"))
     {
-        TRACE("Loading config %s...\n", str);
-        al::ifstream f{str};
+        TRACE("Loading config %s...\n", confname->c_str());
+        al::ifstream f{*confname};
         if(f.is_open())
             LoadConfigFromFile(f);
     }
diff --git a/alc/alu.cpp b/alc/alu.cpp
index 8cef4228..aebb2236 100644
--- a/alc/alu.cpp
+++ b/alc/alu.cpp
@@ -73,6 +73,7 @@
 #include "mixer/defs.h"
 #include "opthelpers.h"
 #include "ringbuffer.h"
+#include "strutils.h"
 #include "threads.h"
 #include "uhjfilter.h"
 #include "vecmat.h"
@@ -87,18 +88,22 @@ using namespace std::placeholders;
 ALfloat InitConeScale()
 {
     ALfloat ret{1.0f};
-    const char *str{getenv("__ALSOFT_HALF_ANGLE_CONES")};
-    if(str && (strcasecmp(str, "true") == 0 || strtol(str, nullptr, 0) == 1))
-        ret *= 0.5f;
+    if(auto optval = al::getenv("__ALSOFT_HALF_ANGLE_CONES"))
+    {
+        if(strcasecmp(optval->c_str(), "true") == 0 || strtol(optval->c_str(), nullptr, 0) == 1)
+            ret *= 0.5f;
+    }
     return ret;
 }
 
 ALfloat InitZScale()
 {
     ALfloat ret{1.0f};
-    const char *str{getenv("__ALSOFT_REVERSE_Z")};
-    if(str && (strcasecmp(str, "true") == 0 || strtol(str, nullptr, 0) == 1))
-        ret *= -1.0f;
+    if(auto optval = al::getenv("__ALSOFT_REVERSE_Z"))
+    {
+        if(strcasecmp(optval->c_str(), "true") == 0 || strtol(optval->c_str(), nullptr, 0) == 1)
+            ret *= -1.0f;
+    }
     return ret;
 }
 
diff --git a/alc/backends/pulseaudio.cpp b/alc/backends/pulseaudio.cpp
index ca2ecb43..499a192f 100644
--- a/alc/backends/pulseaudio.cpp
+++ b/alc/backends/pulseaudio.cpp
@@ -40,6 +40,7 @@
 #include "alexcpt.h"
 #include "compat.h"
 #include "dynload.h"
+#include "strutils.h"
 
 #include <pulse/pulseaudio.h>
 
@@ -855,8 +856,8 @@ ALCenum PulsePlayback::open(const ALCchar *name)
 
     if(!pulse_name)
     {
-        pulse_name = getenv("ALSOFT_PULSE_DEFAULT");
-        if(pulse_name && !pulse_name[0]) pulse_name = nullptr;
+        static const auto defname = al::getenv("ALSOFT_PULSE_DEFAULT");
+        if(defname) pulse_name = defname->c_str();
     }
     TRACE("Connecting to \"%s\"\n", pulse_name ? pulse_name : "(default)");
     mStream = pulse_connect_stream(pulse_name, plock, mContext, flags, nullptr, &spec, nullptr,
diff --git a/alc/helpers.cpp b/alc/helpers.cpp
index 27219b03..daf09de0 100644
--- a/alc/helpers.cpp
+++ b/alc/helpers.cpp
@@ -530,22 +530,21 @@ al::vector<std::string> SearchDataFiles(const char *ext, const char *subdir)
     std::string path;
 
     /* Search the app-local directory. */
-    WCHAR *cwdbuf{_wgetenv(L"ALSOFT_LOCAL_PATH")};
-    if(cwdbuf && *cwdbuf != '\0')
+    if(auto localpath = al::getenv(L"ALSOFT_LOCAL_PATH"))
     {
-        path = wstr_to_utf8(cwdbuf);
+        path = wstr_to_utf8(localpath->c_str());
         if(is_slash(path.back()))
             path.pop_back();
     }
-    else if(!(cwdbuf=_wgetcwd(nullptr, 0)))
-        path = ".";
-    else
+    else if(WCHAR *cwdbuf{_wgetcwd(nullptr, 0)})
     {
         path = wstr_to_utf8(cwdbuf);
         if(is_slash(path.back()))
             path.pop_back();
         free(cwdbuf);
     }
+    else
+        path = ".";
     std::replace(path.begin(), path.end(), '/', '\\');
     DirectorySearch(path.c_str(), ext, &results);
 
@@ -725,9 +724,8 @@ al::vector<std::string> SearchDataFiles(const char *ext, const char *subdir)
     }
 
     /* Search the app-local directory. */
-    const char *str{getenv("ALSOFT_LOCAL_PATH")};
-    if(str && *str != '\0')
-        DirectorySearch(str, ext, &results);
+    if(auto localpath = al::getenv("ALSOFT_LOCAL_PATH"))
+        DirectorySearch(localpath->c_str(), ext, &results);
     else
     {
         al::vector<char> cwdbuf(256);
@@ -750,17 +748,17 @@ al::vector<std::string> SearchDataFiles(const char *ext, const char *subdir)
     }
 
     // Search local data dir
-    if((str=getenv("XDG_DATA_HOME")) != nullptr && str[0] != '\0')
+    if(auto datapath = al::getenv("XDG_DATA_HOME"))
     {
-        std::string path{str};
+        std::string &path = *datapath;
         if(path.back() != '/')
             path += '/';
         path += subdir;
         DirectorySearch(path.c_str(), ext, &results);
     }
-    else if((str=getenv("HOME")) != nullptr && str[0] != '\0')
+    else if(auto homepath = al::getenv("HOME"))
     {
-        std::string path{str};
+        std::string &path = *homepath;
         if(path.back() == '/')
             path.pop_back();
         path += "/.local/share/";
@@ -769,17 +767,18 @@ al::vector<std::string> SearchDataFiles(const char *ext, const char *subdir)
     }
 
     // Search global data dirs
-    if((str=getenv("XDG_DATA_DIRS")) == nullptr || str[0] == '\0')
-        str = "/usr/local/share/:/usr/share/";
+    std::string datadirs{al::getenv("XDG_DATA_DIRS").value_or("/usr/local/share/:/usr/share/")};
 
-    const char *next{str};
-    while((str=next) != nullptr && str[0] != '\0')
+    size_t curpos{0u};
+    while(curpos < datadirs.size())
     {
-        next = strchr(str, ':');
+        size_t nextpos{datadirs.find(':', curpos)};
 
-        std::string path = (next ? std::string(str, next++) : std::string(str));
-        if(path.empty()) continue;
+        std::string path{(nextpos != std::string::npos) ?
+            datadirs.substr(curpos, nextpos++ - curpos) : datadirs.substr(curpos)};
+        curpos = nextpos;
 
+        if(path.empty()) continue;
         if(path.back() != '/')
             path += '/';
         path += subdir;
diff --git a/common/strutils.cpp b/common/strutils.cpp
new file mode 100644
index 00000000..0163de7b
--- /dev/null
+++ b/common/strutils.cpp
@@ -0,0 +1,27 @@
+
+#include "config.h"
+
+#include "strutils.h"
+
+#include <cstdlib>
+
+
+namespace al {
+
+al::optional<std::string> getenv(const char *envname)
+{
+    const char *str{std::getenv(envname)};
+    if(str && str[0] != '\0') return str;
+    return al::nullopt;
+}
+
+#ifdef _WIN32
+al::optional<std::wstring> getenv(const WCHAR *envname)
+{
+    const WCHAR *str{_wgetenv(envname)};
+    if(str && str[0] != L'\0') return str;
+    return al::nullopt;
+}
+#endif
+
+} // namespace al
diff --git a/common/strutils.h b/common/strutils.h
index 2bfd15fc..db9b07c6 100644
--- a/common/strutils.h
+++ b/common/strutils.h
@@ -1,12 +1,14 @@
 #ifndef AL_STRUTILS_H
 #define AL_STRUTILS_H
 
-#ifdef _WIN32
+#include <string>
+
+#include "aloptional.h"
 
+#ifdef _WIN32
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
 
-#include <string>
 
 inline std::string wstr_to_utf8(const WCHAR *wstr)
 {
@@ -40,4 +42,13 @@ inline std::wstring utf8_to_wstr(const char *str)
 
 #endif
 
+namespace al {
+
+al::optional<std::string> getenv(const char *envname);
+#ifdef _WIN32
+al::optional<std::wstring> getenv(const WCHAR *envname);
+#endif
+
+} // namespace al
+
 #endif /* AL_STRUTILS_H */