From 2fc5ad143a89acad80e4b1cf99ceeb9d1461c58d Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 09:04:42 +1300
Subject: [PATCH 01/11] Added USE_IOS(i) and IOS_OR_POSIX(i, p) convenience
 macros.

---
 include/mega/types.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/mega/types.h b/include/mega/types.h
index 4b9bda1aef..009c9593f1 100644
--- a/include/mega/types.h
+++ b/include/mega/types.h
@@ -1480,4 +1480,17 @@ class CheckableMutex<T, true>
 
 using detail::CheckableMutex;
 
+// For convenience.
+#ifdef USE_IOS
+
+#define IOS_ONLY(i) i
+#define IOS_OR_POSIX(i, p) i
+
+#else  // USE_IOS
+
+#define IOS_ONLY(i)
+#define IOS_OR_POSIX(i, p) p
+
+#endif // ! USE_IOS
+
 #endif

From a5dad74aa200be5919478974429c4e054ab305e9 Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 09:14:07 +1300
Subject: [PATCH 02/11] Added LocalPath::rawValue() accessor function.

Present only to reduce the expanding necessity of friend declarations.
---
 include/mega/filesystem.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/include/mega/filesystem.h b/include/mega/filesystem.h
index ee500d43ba..2a08174954 100644
--- a/include/mega/filesystem.h
+++ b/include/mega/filesystem.h
@@ -338,6 +338,16 @@ class MEGA_API LocalPath
     bool operator==(const LocalPath& p) const { return localpath == p.localpath; }
     bool operator!=(const LocalPath& p) const { return localpath != p.localpath; }
     bool operator<(const LocalPath& p) const { return localpath < p.localpath; }
+
+    // Try to avoid using this function as much as you can.
+    //
+    // It's present for efficiency reasons and is really only meant for
+    // specific cases when we are using a LocalPath instance in a system
+    // call.
+    const string_type& rawValue() const
+    {
+        return localpath;
+    }
 };
 
 inline std::ostream& operator<<(std::ostream& os, const LocalPath& p)

From b6417c27e8063fde4a730108380a6e60657f263e Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 09:40:33 +1300
Subject: [PATCH 03/11] Added new AdjustBasePath(...) function.

---
 include/mega/posix/megafs.h |   8 +++
 src/posix/fs.cpp            | 119 ++++++++++++++++++++++++++----------
 2 files changed, 94 insertions(+), 33 deletions(-)

diff --git a/include/mega/posix/megafs.h b/include/mega/posix/megafs.h
index 03441f09f6..e8960cba20 100644
--- a/include/mega/posix/megafs.h
+++ b/include/mega/posix/megafs.h
@@ -44,6 +44,14 @@
 #define DEBRISFOLDER ".debris"
 
 namespace mega {
+
+namespace detail {
+
+auto AdjustBasePath(const LocalPath& path)
+  -> IOS_OR_POSIX(std::string, const std::string&);
+
+} // detail
+
 struct MEGA_API PosixDirAccess : public DirAccess
 {
     DIR* dp;
diff --git a/src/posix/fs.cpp b/src/posix/fs.cpp
index 152220d51e..faa8c8a22a 100644
--- a/src/posix/fs.cpp
+++ b/src/posix/fs.cpp
@@ -110,8 +110,61 @@ extern JavaVM *MEGAjvm;
 #endif /* __APPLE__ || USE_IOS */
 
 namespace mega {
+
+namespace detail {
+
+#ifdef USE_IOS
+
+static std::string GetBasePath()
+{
+    static std::string    basePath;
+    static std::once_flag onceOnly;
+
+    // Compute base path as necessary.
+    std::call_once(onceOnly, []() {
+        ios_appbasepath(&basePath);
+    });
+
+    // Return base path to caller.
+    return basePath;
+}
+
+auto AdjustBasePath(const LocalPath& path) -> std::string
+{
+    // Get our hands on the app's base path.
+    auto basePath = GetBasePath();
+
+    // No base path.
+    if (basePath.empty())
+        return path.rawValue();
+
+    // Path is absolute.
+    if (path.beginsWithSeparator())
+        return path.rawValue();
+
+    // Compute absolute path.
+    basePath.append(path.rawValue());
+
+    // Return absolute path to caller.
+    return basePath;
+}
+
+#else // USE_IOS
+
+auto AdjustBasePath(const LocalPath& path) -> const std::string&
+{
+    return path.rawValue();
+}
+
+#endif // ! USE_IOS
+
+} // detail
+
 using namespace std;
 
+// Make AdjustBasePath visible in current scope.
+using detail::AdjustBasePath;
+
 bool PosixFileAccess::mFoundASymlink = false;
 
 void FileSystemAccess::setMinimumDirectoryPermissions(int permissions)
@@ -231,10 +284,10 @@ PosixFileAccess::~PosixFileAccess()
 bool PosixFileAccess::sysstat(m_time_t* mtime, m_off_t* size, FSLogging)
 {
 #ifdef USE_IOS
-    const string nameStr = adjustBasePath(nonblocking_localname);
+    const string nameStr = AdjustBasePath(nonblocking_localname);
 #else
     // use the existing string if it's not iOS, no need for a copy
-    const string& nameStr = adjustBasePath(nonblocking_localname);
+    const string& nameStr = AdjustBasePath(nonblocking_localname);
 #endif
 
     struct stat statbuf;
@@ -285,13 +338,13 @@ bool PosixFileAccess::sysopen(bool, FSLogging fsl)
     // this is ok: this is not called with mFollowSymLinks = false, but from transfers doio.
     // When fully supporting symlinks, this might need to be reassessed
 
-    fd = open(adjustBasePath(nonblocking_localname).c_str(), O_RDONLY);
+    fd = open(AdjustBasePath(nonblocking_localname).c_str(), O_RDONLY);
     if (fd < 0)
     {
         errorcode = errno;
         if (fsl.doLog(errorcode))
         {
-            LOG_err << "Failed to open('" << adjustBasePath(nonblocking_localname) << "'): error " << errorcode << ": " << PosixFileSystemAccess::getErrorMessage(errorcode);
+            LOG_err << "Failed to open('" << AdjustBasePath(nonblocking_localname) << "'): error " << errorcode << ": " << PosixFileSystemAccess::getErrorMessage(errorcode);
         }
     }
 
@@ -553,10 +606,10 @@ bool PosixFileAccess::fopen(const LocalPath& f, bool read, bool write, FSLogging
     }
 
 #ifdef USE_IOS
-    const string fstr = adjustBasePath(f);
+    const string fstr = AdjustBasePath(f);
 #else
     // use the existing string if it's not iOS, no need for a copy
-    const string& fstr = adjustBasePath(f);
+    const string& fstr = AdjustBasePath(f);
 #endif
 
 
@@ -979,12 +1032,12 @@ bool PosixFileSystemAccess::getsname(const LocalPath&, LocalPath&) const
 bool PosixFileSystemAccess::renamelocal(const LocalPath& oldname, const LocalPath& newname, bool override)
 {
 #ifdef USE_IOS
-    const string oldnamestr = adjustBasePath(oldname);
-    const string newnamestr = adjustBasePath(newname);
+    const string oldnamestr = AdjustBasePath(oldname);
+    const string newnamestr = AdjustBasePath(newname);
 #else
     // use the existing string if it's not iOS, no need for a copy
-    const string& oldnamestr = adjustBasePath(oldname);
-    const string& newnamestr = adjustBasePath(newname);
+    const string& oldnamestr = AdjustBasePath(oldname);
+    const string& newnamestr = AdjustBasePath(newname);
 #endif
 
     bool existingandcare = !override && (0 == access(newnamestr.c_str(), F_OK));
@@ -1009,12 +1062,12 @@ bool PosixFileSystemAccess::renamelocal(const LocalPath& oldname, const LocalPat
 bool PosixFileSystemAccess::copylocal(const LocalPath& oldname, const LocalPath& newname, m_time_t mtime)
 {
 #ifdef USE_IOS
-    const string oldnamestr = adjustBasePath(oldname);
-    const string newnamestr = adjustBasePath(newname);
+    const string oldnamestr = AdjustBasePath(oldname);
+    const string newnamestr = AdjustBasePath(newname);
 #else
     // use the existing string if it's not iOS, no need for a copy
-    const string& oldnamestr = adjustBasePath(oldname);
-    const string& newnamestr = adjustBasePath(newname);
+    const string& oldnamestr = AdjustBasePath(oldname);
+    const string& newnamestr = AdjustBasePath(newname);
 #endif
 
     int sfd, tfd;
@@ -1078,7 +1131,7 @@ bool PosixFileSystemAccess::copylocal(const LocalPath& oldname, const LocalPath&
 
 bool PosixFileSystemAccess::unlinklocal(const LocalPath& name)
 {
-    if (!unlink(adjustBasePath(name).c_str()))
+    if (!unlink(AdjustBasePath(name).c_str()))
     {
         return true;
     }
@@ -1099,9 +1152,9 @@ void PosixFileSystemAccess::emptydirlocal(const LocalPath& nameParam, dev_t base
     int removed;
     struct stat statbuf;
 #ifdef USE_IOS
-    const string namestr = adjustBasePath(name);
+    const string namestr = AdjustBasePath(name);
 #else
-    const string& namestr = adjustBasePath(name);
+    const string& namestr = AdjustBasePath(name);
 #endif
 
     if (!basedev)
@@ -1133,10 +1186,10 @@ void PosixFileSystemAccess::emptydirlocal(const LocalPath& nameParam, dev_t base
                     name.appendWithSeparator(LocalPath::fromPlatformEncodedRelative(d->d_name), true);
 
 #ifdef USE_IOS
-                    const string nameStr = adjustBasePath(name);
+                    const string nameStr = AdjustBasePath(name);
 #else
                     // use the existing string if it's not iOS, no need for a copy
-                    const string& nameStr = adjustBasePath(name);
+                    const string& nameStr = AdjustBasePath(name);
 #endif
                     if (!lstat(nameStr.c_str(), &statbuf))
                     {
@@ -1195,7 +1248,7 @@ bool PosixFileSystemAccess::rmdirlocal(const LocalPath& name)
 {
     emptydirlocal(name);
 
-    if (!rmdir(adjustBasePath(name).c_str()))
+    if (!rmdir(AdjustBasePath(name).c_str()))
     {
         return true;
     }
@@ -1208,10 +1261,10 @@ bool PosixFileSystemAccess::rmdirlocal(const LocalPath& name)
 bool PosixFileSystemAccess::mkdirlocal(const LocalPath& name, bool, bool logAlreadyExistsError)
 {
 #ifdef USE_IOS
-    const string nameStr = adjustBasePath(name);
+    const string nameStr = AdjustBasePath(name);
 #else
     // use the existing string if it's not iOS, no need for a copy
-    const string& nameStr = adjustBasePath(name);
+    const string& nameStr = AdjustBasePath(name);
 #endif
 
     mode_t mode = umask(0);
@@ -1243,10 +1296,10 @@ bool PosixFileSystemAccess::mkdirlocal(const LocalPath& name, bool, bool logAlre
 bool PosixFileSystemAccess::setmtimelocal(const LocalPath& name, m_time_t mtime)
 {
 #ifdef USE_IOS
-    const string nameStr = adjustBasePath(name);
+    const string nameStr = AdjustBasePath(name);
 #else
     // use the existing string if it's not iOS, no need for a copy
-    const string& nameStr = adjustBasePath(name);
+    const string& nameStr = AdjustBasePath(name);
 #endif
 
     struct utimbuf times = { (time_t)mtime, (time_t)mtime };
@@ -1263,7 +1316,7 @@ bool PosixFileSystemAccess::setmtimelocal(const LocalPath& name, m_time_t mtime)
 
 bool PosixFileSystemAccess::chdirlocal(LocalPath& name) const
 {
-    return !chdir(adjustBasePath(name).c_str());
+    return !chdir(AdjustBasePath(name).c_str());
 }
 
 // return lowercased ASCII file extension, including the . separator
@@ -2296,10 +2349,10 @@ bool PosixFileSystemAccess::fsStableIDs(const LocalPath& path) const
 
 bool PosixFileSystemAccess::hardLink(const LocalPath& source, const LocalPath& target)
 {
-    using StringType = decltype(adjustBasePath(source));
+    using StringType = decltype(AdjustBasePath(source));
 
-    StringType sourcePath = adjustBasePath(source);
-    StringType targetPath = adjustBasePath(target);
+    StringType sourcePath = AdjustBasePath(source);
+    StringType targetPath = AdjustBasePath(target);
 
     if (link(sourcePath.c_str(), targetPath.c_str()))
     {
@@ -2448,7 +2501,7 @@ bool PosixDirAccess::dopen(LocalPath* path, FileAccess* f, bool doglob)
 {
     if (doglob)
     {
-        if (glob(adjustBasePath(*path).c_str(), GLOB_NOSORT, NULL, &globbuf))
+        if (glob(AdjustBasePath(*path).c_str(), GLOB_NOSORT, NULL, &globbuf))
         {
             return false;
         }
@@ -2470,7 +2523,7 @@ bool PosixDirAccess::dopen(LocalPath* path, FileAccess* f, bool doglob)
     }
     else
     {
-        dp = opendir(adjustBasePath(*path).c_str());
+        dp = opendir(AdjustBasePath(*path).c_str());
     }
 
     return dp != NULL;
@@ -2514,10 +2567,10 @@ bool PosixDirAccess::dnext(LocalPath& path, LocalPath& name, bool followsymlinks
             path.appendWithSeparator(LocalPath::fromPlatformEncodedRelative(d->d_name), true);
 
 #ifdef USE_IOS
-            const string pathStr = adjustBasePath(path);
+            const string pathStr = AdjustBasePath(path);
 #else
             // use the existing string if it's not iOS, no need for a copy
-            const string& pathStr = adjustBasePath(path);
+            const string& pathStr = AdjustBasePath(path);
 #endif
 
             bool statOk = !lstat(pathStr.c_str(), &statbuf);
@@ -2581,7 +2634,7 @@ m_off_t PosixFileSystemAccess::availableDiskSpace(const LocalPath& drivePath)
     struct statfs buffer;
     m_off_t constexpr maximumBytes = std::numeric_limits<m_off_t>::max();
 
-    if (statfs(adjustBasePath(drivePath).c_str(), &buffer) < 0)
+    if (statfs(AdjustBasePath(drivePath).c_str(), &buffer) < 0)
     {
         auto result = errno;
 

From d170fda5ad0b5d2ecbb1d0b756ad59c57ad5edd0 Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 09:46:56 +1300
Subject: [PATCH 04/11] Simplify use of AdjustBasePath(...).

---
 include/mega/posix/megafs.h |  6 ++-
 src/posix/fs.cpp            | 81 ++++++++-----------------------------
 2 files changed, 21 insertions(+), 66 deletions(-)

diff --git a/include/mega/posix/megafs.h b/include/mega/posix/megafs.h
index e8960cba20..76af35d9d0 100644
--- a/include/mega/posix/megafs.h
+++ b/include/mega/posix/megafs.h
@@ -47,8 +47,10 @@ namespace mega {
 
 namespace detail {
 
-auto AdjustBasePath(const LocalPath& path)
-  -> IOS_OR_POSIX(std::string, const std::string&);
+using AdjustBasePathResult =
+  IOS_OR_POSIX(std::string, const std::string&);
+
+AdjustBasePathResult AdjustBasePath(const LocalPath& path);
 
 } // detail
 
diff --git a/src/posix/fs.cpp b/src/posix/fs.cpp
index faa8c8a22a..a7b9daa42d 100644
--- a/src/posix/fs.cpp
+++ b/src/posix/fs.cpp
@@ -129,7 +129,7 @@ static std::string GetBasePath()
     return basePath;
 }
 
-auto AdjustBasePath(const LocalPath& path) -> std::string
+AdjustBasePathResult AdjustBasePath(const LocalPath& path)
 {
     // Get our hands on the app's base path.
     auto basePath = GetBasePath();
@@ -151,7 +151,7 @@ auto AdjustBasePath(const LocalPath& path) -> std::string
 
 #else // USE_IOS
 
-auto AdjustBasePath(const LocalPath& path) -> const std::string&
+AdjustBasePathResult AdjustBasePath(const LocalPath& path)
 {
     return path.rawValue();
 }
@@ -164,6 +164,7 @@ using namespace std;
 
 // Make AdjustBasePath visible in current scope.
 using detail::AdjustBasePath;
+using detail::AdjustBasePathResult;
 
 bool PosixFileAccess::mFoundASymlink = false;
 
@@ -283,12 +284,7 @@ PosixFileAccess::~PosixFileAccess()
 
 bool PosixFileAccess::sysstat(m_time_t* mtime, m_off_t* size, FSLogging)
 {
-#ifdef USE_IOS
-    const string nameStr = AdjustBasePath(nonblocking_localname);
-#else
-    // use the existing string if it's not iOS, no need for a copy
-    const string& nameStr = AdjustBasePath(nonblocking_localname);
-#endif
+    AdjustBasePathResult nameStr = AdjustBasePath(nonblocking_localname);
 
     struct stat statbuf;
     retry = false;
@@ -605,13 +601,7 @@ bool PosixFileAccess::fopen(const LocalPath& f, bool read, bool write, FSLogging
         statok = true;
     }
 
-#ifdef USE_IOS
-    const string fstr = AdjustBasePath(f);
-#else
-    // use the existing string if it's not iOS, no need for a copy
-    const string& fstr = AdjustBasePath(f);
-#endif
-
+    AdjustBasePathResult fstr = AdjustBasePath(f);
 
 #ifdef __MACH__
     if (!write)
@@ -1031,14 +1021,8 @@ bool PosixFileSystemAccess::getsname(const LocalPath&, LocalPath&) const
 
 bool PosixFileSystemAccess::renamelocal(const LocalPath& oldname, const LocalPath& newname, bool override)
 {
-#ifdef USE_IOS
-    const string oldnamestr = AdjustBasePath(oldname);
-    const string newnamestr = AdjustBasePath(newname);
-#else
-    // use the existing string if it's not iOS, no need for a copy
-    const string& oldnamestr = AdjustBasePath(oldname);
-    const string& newnamestr = AdjustBasePath(newname);
-#endif
+    AdjustBasePathResult oldnamestr = AdjustBasePath(oldname);
+    AdjustBasePathResult newnamestr = AdjustBasePath(newname);
 
     bool existingandcare = !override && (0 == access(newnamestr.c_str(), F_OK));
     if (!existingandcare && !rename(oldnamestr.c_str(), newnamestr.c_str()))
@@ -1061,14 +1045,8 @@ bool PosixFileSystemAccess::renamelocal(const LocalPath& oldname, const LocalPat
 
 bool PosixFileSystemAccess::copylocal(const LocalPath& oldname, const LocalPath& newname, m_time_t mtime)
 {
-#ifdef USE_IOS
-    const string oldnamestr = AdjustBasePath(oldname);
-    const string newnamestr = AdjustBasePath(newname);
-#else
-    // use the existing string if it's not iOS, no need for a copy
-    const string& oldnamestr = AdjustBasePath(oldname);
-    const string& newnamestr = AdjustBasePath(newname);
-#endif
+    AdjustBasePathResult oldnamestr = AdjustBasePath(oldname);
+    AdjustBasePathResult newnamestr = AdjustBasePath(newname);
 
     int sfd, tfd;
     ssize_t t = -1;
@@ -1151,11 +1129,7 @@ void PosixFileSystemAccess::emptydirlocal(const LocalPath& nameParam, dev_t base
     dirent* d;
     int removed;
     struct stat statbuf;
-#ifdef USE_IOS
-    const string namestr = AdjustBasePath(name);
-#else
-    const string& namestr = AdjustBasePath(name);
-#endif
+    AdjustBasePathResult namestr = AdjustBasePath(name);
 
     if (!basedev)
     {
@@ -1185,12 +1159,8 @@ void PosixFileSystemAccess::emptydirlocal(const LocalPath& nameParam, dev_t base
 
                     name.appendWithSeparator(LocalPath::fromPlatformEncodedRelative(d->d_name), true);
 
-#ifdef USE_IOS
-                    const string nameStr = AdjustBasePath(name);
-#else
-                    // use the existing string if it's not iOS, no need for a copy
-                    const string& nameStr = AdjustBasePath(name);
-#endif
+                    AdjustBasePathResult nameStr = AdjustBasePath(name);
+
                     if (!lstat(nameStr.c_str(), &statbuf))
                     {
                         if (!S_ISLNK(statbuf.st_mode) && S_ISDIR(statbuf.st_mode) && statbuf.st_dev == basedev)
@@ -1260,12 +1230,7 @@ bool PosixFileSystemAccess::rmdirlocal(const LocalPath& name)
 
 bool PosixFileSystemAccess::mkdirlocal(const LocalPath& name, bool, bool logAlreadyExistsError)
 {
-#ifdef USE_IOS
-    const string nameStr = AdjustBasePath(name);
-#else
-    // use the existing string if it's not iOS, no need for a copy
-    const string& nameStr = AdjustBasePath(name);
-#endif
+    AdjustBasePathResult nameStr = AdjustBasePath(name);
 
     mode_t mode = umask(0);
     bool r = !mkdir(nameStr.c_str(), defaultfolderpermissions);
@@ -1295,12 +1260,7 @@ bool PosixFileSystemAccess::mkdirlocal(const LocalPath& name, bool, bool logAlre
 
 bool PosixFileSystemAccess::setmtimelocal(const LocalPath& name, m_time_t mtime)
 {
-#ifdef USE_IOS
-    const string nameStr = AdjustBasePath(name);
-#else
-    // use the existing string if it's not iOS, no need for a copy
-    const string& nameStr = AdjustBasePath(name);
-#endif
+    AdjustBasePathResult nameStr = AdjustBasePath(name);
 
     struct utimbuf times = { (time_t)mtime, (time_t)mtime };
 
@@ -2349,10 +2309,8 @@ bool PosixFileSystemAccess::fsStableIDs(const LocalPath& path) const
 
 bool PosixFileSystemAccess::hardLink(const LocalPath& source, const LocalPath& target)
 {
-    using StringType = decltype(AdjustBasePath(source));
-
-    StringType sourcePath = AdjustBasePath(source);
-    StringType targetPath = AdjustBasePath(target);
+    AdjustBasePathResult sourcePath = AdjustBasePath(source);
+    AdjustBasePathResult targetPath = AdjustBasePath(target);
 
     if (link(sourcePath.c_str(), targetPath.c_str()))
     {
@@ -2566,12 +2524,7 @@ bool PosixDirAccess::dnext(LocalPath& path, LocalPath& name, bool followsymlinks
         {
             path.appendWithSeparator(LocalPath::fromPlatformEncodedRelative(d->d_name), true);
 
-#ifdef USE_IOS
-            const string pathStr = AdjustBasePath(path);
-#else
-            // use the existing string if it's not iOS, no need for a copy
-            const string& pathStr = AdjustBasePath(path);
-#endif
+            AdjustBasePathResult pathStr = AdjustBasePath(path);
 
             bool statOk = !lstat(pathStr.c_str(), &statbuf);
             if (followsymlinks && statOk && S_ISLNK(statbuf.st_mode))

From fc1b2cde811f79a982027513aebfc45b66091c57 Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 09:48:12 +1300
Subject: [PATCH 05/11] Remove old adjustBasePath(...) code.

---
 include/mega/posix/megafs.h |  4 ----
 src/posix/fs.cpp            | 41 -------------------------------------
 2 files changed, 45 deletions(-)

diff --git a/include/mega/posix/megafs.h b/include/mega/posix/megafs.h
index 76af35d9d0..d55e57c755 100644
--- a/include/mega/posix/megafs.h
+++ b/include/mega/posix/megafs.h
@@ -76,10 +76,6 @@ class MEGA_API PosixFileSystemAccess : public FileSystemAccess
 public:
     using FileSystemAccess::getlocalfstype;
 
-#ifdef USE_IOS
-    static char *appbasepath;
-#endif
-
     int defaultfilepermissions;
     int defaultfolderpermissions;
 
diff --git a/src/posix/fs.cpp b/src/posix/fs.cpp
index a7b9daa42d..99a84d217b 100644
--- a/src/posix/fs.cpp
+++ b/src/posix/fs.cpp
@@ -178,34 +178,6 @@ void FileSystemAccess::setMinimumFilePermissions(int permissions)
     mMinimumFilePermissions = permissions & 07777;
 }
 
-#ifdef USE_IOS
-
-const string adjustBasePath(const LocalPath& name)
-{
-    // return a temporary variable that the caller can optionally use c_str on (in that expression)
-    if (PosixFileSystemAccess::appbasepath)
-    {
-        if (!name.beginsWithSeparator())
-        {
-            string absolutename = PosixFileSystemAccess::appbasepath;
-            absolutename.append(name.localpath);
-            return absolutename;
-        }
-    }
-    return name.localpath;
-}
-
-char* PosixFileSystemAccess::appbasepath = nullptr;
-
-#else /* USE_IOS */
-
-const string& adjustBasePath(const LocalPath& name)
-{
-    return name.localpath;
-}
-
-#endif /* ! USE_IOS */
-
 int platformCompareUtf(const string& p1, bool unescape1, const string& p2, bool unescape2)
 {
     return compareUtf(p1, unescape1, p2, unescape2, false);
@@ -801,19 +773,6 @@ PosixFileSystemAccess::PosixFileSystemAccess()
 
     defaultfilepermissions = 0600;
     defaultfolderpermissions = 0700;
-
-#ifdef USE_IOS
-    if (!appbasepath)
-    {
-        string basepath;
-        ios_appbasepath(&basepath);
-        if (basepath.size())
-        {
-            basepath.append("/");
-            appbasepath = strdup(basepath.c_str());
-        }
-    }
-#endif
 }
 
 #ifdef __linux__

From fb1939211561b94d1c4190a444cfad9fa1d9c3f6 Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 09:55:16 +1300
Subject: [PATCH 06/11] Don't use Disk Arbitration on iOS.

---
 src/osx/fs.cpp | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/osx/fs.cpp b/src/osx/fs.cpp
index 87ce781646..50eac835b0 100644
--- a/src/osx/fs.cpp
+++ b/src/osx/fs.cpp
@@ -1,7 +1,10 @@
 #include <sys/mount.h>
 #include <sys/param.h>
 
-#include <DiskArbitration/DADisk.h>
+// Disk Arbitration is not available on iOS.
+#ifndef USE_IOS
+#    include <DiskArbitration/DADisk.h>
+#endif // ! USE_IOS
 
 #include <cassert>
 #include <future>
@@ -117,6 +120,8 @@ static DeviceOfResult deviceOf(const std::string& path)
     return result;
 }
 
+#ifndef USE_IOS
+
 static std::string uuidOf(const std::string& device)
 {
     // Convenience.
@@ -230,21 +235,33 @@ static std::string uuidOf(const std::string& device)
     return std::string();
 }
 
+#endif // ! USE_IOS
+
 fsfp_t FileSystemAccess::fsFingerprint(const LocalPath& path) const
 {
-    auto device = deviceOf(path.localpath);
+    // Convenience.
+    using detail::AdjustBasePath;
+
+    // What device contains path?
+    auto device = deviceOf(AdjustBasePath(path));
     
     // Couldn't determine which device contains path.
     if (device.first.empty())
         return fsfp_t();
 
+    std::string uuid;
+
+#ifndef USE_IOS
+
     // Try and determine the device's UUID.
-    auto uuid = uuidOf(device.first);
+    uuid = uuidOf(device.first);
 
     // Couldn't determine UUID.
     if (uuid.empty())
         return fsfp_t();
 
+#endif // ! USE_IOS
+
     // Return fingerprint to caller.
     return fsfp_t(device.second, std::move(uuid));
 }

From fd19485dc616f65ad40221da9563808ad98ae917 Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 12:34:15 +1300
Subject: [PATCH 07/11] Fix iOS compilation failure.

---
 src/osx/fs.cpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/osx/fs.cpp b/src/osx/fs.cpp
index 50eac835b0..a024be09cf 100644
--- a/src/osx/fs.cpp
+++ b/src/osx/fs.cpp
@@ -1,16 +1,16 @@
 #include <sys/mount.h>
 #include <sys/param.h>
 
-// Disk Arbitration is not available on iOS.
-#ifndef USE_IOS
-#    include <DiskArbitration/DADisk.h>
-#endif // ! USE_IOS
-
 #include <cassert>
 #include <future>
 
 #include "mega.h"
 
+// Disk Arbitration is not available on iOS.
+#ifndef USE_IOS
+#    include <DiskArbitration/DADisk.h>
+#endif // ! USE_IOS
+
 namespace mega {
 
 // Convenience.

From f8569fbe31fc62285e8c22f672b25ffedccb0bfe Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 12:34:55 +1300
Subject: [PATCH 08/11] adjustBasePath(...) no longer needs to be friends with
 LocalPath.

---
 include/mega/filesystem.h | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/include/mega/filesystem.h b/include/mega/filesystem.h
index 2a08174954..0948162b86 100644
--- a/include/mega/filesystem.h
+++ b/include/mega/filesystem.h
@@ -198,11 +198,7 @@ class MEGA_API LocalPath
     friend void AddHiddenFileAttribute(LocalPath& path);
     friend class GfxProviderFreeImage;
     friend struct FileSystemAccess;
-#ifdef USE_IOS
-    friend const string adjustBasePath(const LocalPath& name);
-#else
-    friend const string& adjustBasePath(const LocalPath& name);
-#endif
+
     friend int compareUtf(const string&, bool unescaping1, const string&, bool unescaping2, bool caseInsensitive);
     friend int compareUtf(const string&, bool unescaping1, const LocalPath&, bool unescaping2, bool caseInsensitive);
     friend int compareUtf(const LocalPath&, bool unescaping1, const string&, bool unescaping2, bool caseInsensitive);

From bb4a98a995322a325e66d50ef957edd7f52f33aa Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 12:38:10 +1300
Subject: [PATCH 09/11] Rename AdjustBasePath -> adjustBasePath.

---
 include/mega/posix/megafs.h |  2 +-
 src/osx/fs.cpp              |  4 ++--
 src/posix/fs.cpp            | 48 ++++++++++++++++++-------------------
 3 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/include/mega/posix/megafs.h b/include/mega/posix/megafs.h
index d55e57c755..6241a835f3 100644
--- a/include/mega/posix/megafs.h
+++ b/include/mega/posix/megafs.h
@@ -50,7 +50,7 @@ namespace detail {
 using AdjustBasePathResult =
   IOS_OR_POSIX(std::string, const std::string&);
 
-AdjustBasePathResult AdjustBasePath(const LocalPath& path);
+AdjustBasePathResult adjustBasePath(const LocalPath& path);
 
 } // detail
 
diff --git a/src/osx/fs.cpp b/src/osx/fs.cpp
index a024be09cf..a2d88ce8c9 100644
--- a/src/osx/fs.cpp
+++ b/src/osx/fs.cpp
@@ -240,10 +240,10 @@ static std::string uuidOf(const std::string& device)
 fsfp_t FileSystemAccess::fsFingerprint(const LocalPath& path) const
 {
     // Convenience.
-    using detail::AdjustBasePath;
+    using detail::adjustBasePath;
 
     // What device contains path?
-    auto device = deviceOf(AdjustBasePath(path));
+    auto device = deviceOf(adjustBasePath(path));
     
     // Couldn't determine which device contains path.
     if (device.first.empty())
diff --git a/src/posix/fs.cpp b/src/posix/fs.cpp
index 99a84d217b..2a574e91f7 100644
--- a/src/posix/fs.cpp
+++ b/src/posix/fs.cpp
@@ -129,7 +129,7 @@ static std::string GetBasePath()
     return basePath;
 }
 
-AdjustBasePathResult AdjustBasePath(const LocalPath& path)
+AdjustBasePathResult adjustBasePath(const LocalPath& path)
 {
     // Get our hands on the app's base path.
     auto basePath = GetBasePath();
@@ -151,7 +151,7 @@ AdjustBasePathResult AdjustBasePath(const LocalPath& path)
 
 #else // USE_IOS
 
-AdjustBasePathResult AdjustBasePath(const LocalPath& path)
+AdjustBasePathResult adjustBasePath(const LocalPath& path)
 {
     return path.rawValue();
 }
@@ -163,7 +163,7 @@ AdjustBasePathResult AdjustBasePath(const LocalPath& path)
 using namespace std;
 
 // Make AdjustBasePath visible in current scope.
-using detail::AdjustBasePath;
+using detail::adjustBasePath;
 using detail::AdjustBasePathResult;
 
 bool PosixFileAccess::mFoundASymlink = false;
@@ -256,7 +256,7 @@ PosixFileAccess::~PosixFileAccess()
 
 bool PosixFileAccess::sysstat(m_time_t* mtime, m_off_t* size, FSLogging)
 {
-    AdjustBasePathResult nameStr = AdjustBasePath(nonblocking_localname);
+    AdjustBasePathResult nameStr = adjustBasePath(nonblocking_localname);
 
     struct stat statbuf;
     retry = false;
@@ -306,13 +306,13 @@ bool PosixFileAccess::sysopen(bool, FSLogging fsl)
     // this is ok: this is not called with mFollowSymLinks = false, but from transfers doio.
     // When fully supporting symlinks, this might need to be reassessed
 
-    fd = open(AdjustBasePath(nonblocking_localname).c_str(), O_RDONLY);
+    fd = open(adjustBasePath(nonblocking_localname).c_str(), O_RDONLY);
     if (fd < 0)
     {
         errorcode = errno;
         if (fsl.doLog(errorcode))
         {
-            LOG_err << "Failed to open('" << AdjustBasePath(nonblocking_localname) << "'): error " << errorcode << ": " << PosixFileSystemAccess::getErrorMessage(errorcode);
+            LOG_err << "Failed to open('" << adjustBasePath(nonblocking_localname) << "'): error " << errorcode << ": " << PosixFileSystemAccess::getErrorMessage(errorcode);
         }
     }
 
@@ -573,7 +573,7 @@ bool PosixFileAccess::fopen(const LocalPath& f, bool read, bool write, FSLogging
         statok = true;
     }
 
-    AdjustBasePathResult fstr = AdjustBasePath(f);
+    AdjustBasePathResult fstr = adjustBasePath(f);
 
 #ifdef __MACH__
     if (!write)
@@ -980,8 +980,8 @@ bool PosixFileSystemAccess::getsname(const LocalPath&, LocalPath&) const
 
 bool PosixFileSystemAccess::renamelocal(const LocalPath& oldname, const LocalPath& newname, bool override)
 {
-    AdjustBasePathResult oldnamestr = AdjustBasePath(oldname);
-    AdjustBasePathResult newnamestr = AdjustBasePath(newname);
+    AdjustBasePathResult oldnamestr = adjustBasePath(oldname);
+    AdjustBasePathResult newnamestr = adjustBasePath(newname);
 
     bool existingandcare = !override && (0 == access(newnamestr.c_str(), F_OK));
     if (!existingandcare && !rename(oldnamestr.c_str(), newnamestr.c_str()))
@@ -1004,8 +1004,8 @@ bool PosixFileSystemAccess::renamelocal(const LocalPath& oldname, const LocalPat
 
 bool PosixFileSystemAccess::copylocal(const LocalPath& oldname, const LocalPath& newname, m_time_t mtime)
 {
-    AdjustBasePathResult oldnamestr = AdjustBasePath(oldname);
-    AdjustBasePathResult newnamestr = AdjustBasePath(newname);
+    AdjustBasePathResult oldnamestr = adjustBasePath(oldname);
+    AdjustBasePathResult newnamestr = adjustBasePath(newname);
 
     int sfd, tfd;
     ssize_t t = -1;
@@ -1068,7 +1068,7 @@ bool PosixFileSystemAccess::copylocal(const LocalPath& oldname, const LocalPath&
 
 bool PosixFileSystemAccess::unlinklocal(const LocalPath& name)
 {
-    if (!unlink(AdjustBasePath(name).c_str()))
+    if (!unlink(adjustBasePath(name).c_str()))
     {
         return true;
     }
@@ -1088,7 +1088,7 @@ void PosixFileSystemAccess::emptydirlocal(const LocalPath& nameParam, dev_t base
     dirent* d;
     int removed;
     struct stat statbuf;
-    AdjustBasePathResult namestr = AdjustBasePath(name);
+    AdjustBasePathResult namestr = adjustBasePath(name);
 
     if (!basedev)
     {
@@ -1118,7 +1118,7 @@ void PosixFileSystemAccess::emptydirlocal(const LocalPath& nameParam, dev_t base
 
                     name.appendWithSeparator(LocalPath::fromPlatformEncodedRelative(d->d_name), true);
 
-                    AdjustBasePathResult nameStr = AdjustBasePath(name);
+                    AdjustBasePathResult nameStr = adjustBasePath(name);
 
                     if (!lstat(nameStr.c_str(), &statbuf))
                     {
@@ -1177,7 +1177,7 @@ bool PosixFileSystemAccess::rmdirlocal(const LocalPath& name)
 {
     emptydirlocal(name);
 
-    if (!rmdir(AdjustBasePath(name).c_str()))
+    if (!rmdir(adjustBasePath(name).c_str()))
     {
         return true;
     }
@@ -1189,7 +1189,7 @@ bool PosixFileSystemAccess::rmdirlocal(const LocalPath& name)
 
 bool PosixFileSystemAccess::mkdirlocal(const LocalPath& name, bool, bool logAlreadyExistsError)
 {
-    AdjustBasePathResult nameStr = AdjustBasePath(name);
+    AdjustBasePathResult nameStr = adjustBasePath(name);
 
     mode_t mode = umask(0);
     bool r = !mkdir(nameStr.c_str(), defaultfolderpermissions);
@@ -1219,7 +1219,7 @@ bool PosixFileSystemAccess::mkdirlocal(const LocalPath& name, bool, bool logAlre
 
 bool PosixFileSystemAccess::setmtimelocal(const LocalPath& name, m_time_t mtime)
 {
-    AdjustBasePathResult nameStr = AdjustBasePath(name);
+    AdjustBasePathResult nameStr = adjustBasePath(name);
 
     struct utimbuf times = { (time_t)mtime, (time_t)mtime };
 
@@ -1235,7 +1235,7 @@ bool PosixFileSystemAccess::setmtimelocal(const LocalPath& name, m_time_t mtime)
 
 bool PosixFileSystemAccess::chdirlocal(LocalPath& name) const
 {
-    return !chdir(AdjustBasePath(name).c_str());
+    return !chdir(adjustBasePath(name).c_str());
 }
 
 // return lowercased ASCII file extension, including the . separator
@@ -2268,8 +2268,8 @@ bool PosixFileSystemAccess::fsStableIDs(const LocalPath& path) const
 
 bool PosixFileSystemAccess::hardLink(const LocalPath& source, const LocalPath& target)
 {
-    AdjustBasePathResult sourcePath = AdjustBasePath(source);
-    AdjustBasePathResult targetPath = AdjustBasePath(target);
+    AdjustBasePathResult sourcePath = adjustBasePath(source);
+    AdjustBasePathResult targetPath = adjustBasePath(target);
 
     if (link(sourcePath.c_str(), targetPath.c_str()))
     {
@@ -2418,7 +2418,7 @@ bool PosixDirAccess::dopen(LocalPath* path, FileAccess* f, bool doglob)
 {
     if (doglob)
     {
-        if (glob(AdjustBasePath(*path).c_str(), GLOB_NOSORT, NULL, &globbuf))
+        if (glob(adjustBasePath(*path).c_str(), GLOB_NOSORT, NULL, &globbuf))
         {
             return false;
         }
@@ -2440,7 +2440,7 @@ bool PosixDirAccess::dopen(LocalPath* path, FileAccess* f, bool doglob)
     }
     else
     {
-        dp = opendir(AdjustBasePath(*path).c_str());
+        dp = opendir(adjustBasePath(*path).c_str());
     }
 
     return dp != NULL;
@@ -2483,7 +2483,7 @@ bool PosixDirAccess::dnext(LocalPath& path, LocalPath& name, bool followsymlinks
         {
             path.appendWithSeparator(LocalPath::fromPlatformEncodedRelative(d->d_name), true);
 
-            AdjustBasePathResult pathStr = AdjustBasePath(path);
+            AdjustBasePathResult pathStr = adjustBasePath(path);
 
             bool statOk = !lstat(pathStr.c_str(), &statbuf);
             if (followsymlinks && statOk && S_ISLNK(statbuf.st_mode))
@@ -2546,7 +2546,7 @@ m_off_t PosixFileSystemAccess::availableDiskSpace(const LocalPath& drivePath)
     struct statfs buffer;
     m_off_t constexpr maximumBytes = std::numeric_limits<m_off_t>::max();
 
-    if (statfs(AdjustBasePath(drivePath).c_str(), &buffer) < 0)
+    if (statfs(adjustBasePath(drivePath).c_str(), &buffer) < 0)
     {
         auto result = errno;
 

From b13342e4317eb9b8c091065cd0758aaea980f80c Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 12:45:46 +1300
Subject: [PATCH 10/11] Add uuidOf(...) stub for iOS.

---
 src/osx/fs.cpp | 41 +++++++++++++++++++++++------------------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/src/osx/fs.cpp b/src/osx/fs.cpp
index a2d88ce8c9..ea2b634303 100644
--- a/src/osx/fs.cpp
+++ b/src/osx/fs.cpp
@@ -120,9 +120,13 @@ static DeviceOfResult deviceOf(const std::string& path)
     return result;
 }
 
+// Convenience.
+using UUIDOfResult =
+  std::pair<std::string, bool>;
+
 #ifndef USE_IOS
 
-static std::string uuidOf(const std::string& device)
+static UUIDOfResult uuidOf(const std::string& device)
 {
     // Convenience.
     using DictionaryPtr = CFPtr<CFDictionaryRef>;
@@ -137,7 +141,7 @@ static std::string uuidOf(const std::string& device)
 
     // Couldn't establish DA session.
     if (!session)
-        return std::string();
+        return UUIDOfResult("", false);
 
     // Try and get a reference to the specified device.
     DiskPtr disk(DADiskCreateFromBSDName(allocator,
@@ -146,14 +150,14 @@ static std::string uuidOf(const std::string& device)
 
     // Couldn't get a reference to the device.
     if (!disk)
-        return std::string();
+        return UUIDOfResult("", false);
 
     // Try and get the device's description.
     DictionaryPtr info(DADiskCopyDescription(disk.get()));
 
     // Couldn't get device's description.
     if (!info)
-        return std::string();
+        return UUIDOfResult("", false);
 
     // What UUIDs do we want to retrieve?
     static const std::vector<const char*> names = {
@@ -177,7 +181,7 @@ static std::string uuidOf(const std::string& device)
 
         // Couldn't create key.
         if (!key)
-            return std::string();
+            return UUIDOfResult("", false);
 
         // Try and retrieve UUID associated with key.
         auto uuid = ([&]() {
@@ -201,7 +205,7 @@ static std::string uuidOf(const std::string& device)
 
         // Try and retrieve the string's raw value.
         if (auto* value = CFStringGetCStringPtr(string.get(), encoding))
-            return value;
+            return UUIDOfResult(value, true);
 
         // Compute necessary buffer length.
         auto required =
@@ -228,14 +232,21 @@ static std::string uuidOf(const std::string& device)
         buffer.resize(static_cast<std::size_t>(required));
 
         // Return UUID to caller.
-        return buffer;
+        return UUIDOfResult(std::move(buffer), true);
     }
 
     // Couldn't retrieve UUID.
-    return std::string();
+    return UUIDOfResult("", false);
 }
 
-#endif // ! USE_IOS
+#else // ! USE_IOS
+
+static UUIDOfResult uuidOf(const std::string&)
+{
+    return UUIDOfResult("", true);
+}
+
+#endif // USE_IOS
 
 fsfp_t FileSystemAccess::fsFingerprint(const LocalPath& path) const
 {
@@ -249,21 +260,15 @@ fsfp_t FileSystemAccess::fsFingerprint(const LocalPath& path) const
     if (device.first.empty())
         return fsfp_t();
 
-    std::string uuid;
-
-#ifndef USE_IOS
-
     // Try and determine the device's UUID.
-    uuid = uuidOf(device.first);
+    auto uuid = uuidOf(device.first);
 
     // Couldn't determine UUID.
-    if (uuid.empty())
+    if (!uuid.second)
         return fsfp_t();
 
-#endif // ! USE_IOS
-
     // Return fingerprint to caller.
-    return fsfp_t(device.second, std::move(uuid));
+    return fsfp_t(device.second, std::move(uuid.first));
 }
 
 MacFileSystemAccess::MacFileSystemAccess()

From 5a66f2a7ca2ce9d72d3032ddbb51d2098c232a40 Mon Sep 17 00:00:00 2001
From: David Ward <dw@mega.co.nz>
Date: Thu, 23 Nov 2023 13:01:15 +1300
Subject: [PATCH 11/11] CG GFXProc now uses adjustBasePath(...).

---
 src/gfx/GfxProcCG.mm | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/gfx/GfxProcCG.mm b/src/gfx/GfxProcCG.mm
index a6ba9fcca2..e901ae06bd 100644
--- a/src/gfx/GfxProcCG.mm
+++ b/src/gfx/GfxProcCG.mm
@@ -55,17 +55,20 @@
     return NULL;
 }
 
-bool GfxProviderCG::readbitmap(FileSystemAccess* fa, const LocalPath& name, int size) {
-    string absolutename;
-    NSString *sourcePath;
-    if (PosixFileSystemAccess::appbasepath && !name.beginsWithSeparator()) {
-        absolutename = PosixFileSystemAccess::appbasepath;
-        absolutename.append(name.platformEncoded());
-        sourcePath = [NSString stringWithCString:absolutename.c_str() encoding:[NSString defaultCStringEncoding]];
-    } else {
-        sourcePath = [NSString stringWithCString:name.platformEncoded().c_str() encoding:[NSString defaultCStringEncoding]];
-    }
-    
+bool GfxProviderCG::readbitmap(FileSystemAccess* fa, const LocalPath& path, int size) {
+    // Convenience.
+    using mega::detail::AdjustBasePathResult;
+    using mega::detail::adjustBasePath;
+
+    // Ensure provided path is absolute.
+    AdjustBasePathResult absolutePath = adjustBasePath(path);
+
+    // Make absolute path usable to Cocoa.
+    NSString* sourcePath =
+      [NSString stringWithCString: absolutePath.c_str()
+                encoding: [NSString defaultCStringEncoding]];
+
+    // Couldn't create a Cocoa-friendly path.
     if (sourcePath == nil) {
         return false;
     }