From d67b83e671f1749cfdb73e251ddc0eae93e3c881 Mon Sep 17 00:00:00 2001
From: Carsten Grohmann <mail@carstengrohmann.de>
Date: Sun, 13 Jun 2021 20:45:56 +0200
Subject: [PATCH] Allow configuration for temporary files directory

---
 Makefile.am            |  1 -
 doc/man/s3fs.1         |  3 ++
 src/fdcache.cpp        | 94 ++++++++++++++++++++++++++++--------------
 src/fdcache.h          |  5 +++
 src/fdcache_entity.cpp |  8 ++--
 src/s3fs.cpp           | 12 ++++++
 src/s3fs_help.cpp      |  3 ++
 7 files changed, 90 insertions(+), 36 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index 3877d0b..ebea5ea 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -37,7 +37,6 @@ cppcheck:
             -D HAVE_SYS_EXTATTR_H \
             -D HAVE_MALLOC_TRIM \
             -U CURLE_PEER_FAILED_VERIFICATION \
-            -U P_tmpdir \
             -U ENOATTR \
             --enable=warning,style,information,missingInclude \
             --suppress=missingIncludeSystem \
diff --git a/doc/man/s3fs.1 b/doc/man/s3fs.1
index 2d840fe..b796693 100644
--- a/doc/man/s3fs.1
+++ b/doc/man/s3fs.1
@@ -70,6 +70,9 @@ see https://docs.aws.amazon.com/AmazonS3/latest/dev/acl-overview.html#canned-acl
 \fB\-o\fR retries (default="5")
 number of times to retry a failed S3 transaction.
 .TP
+\fB\-o\fR tmpdir (default="/tmp")
+local folder for temporary files.
+.TP
 \fB\-o\fR use_cache (default="" which means disabled)
 local folder to use for local file cache.
 .TP
diff --git a/src/fdcache.cpp b/src/fdcache.cpp
index 4f93145..83a18b4 100644
--- a/src/fdcache.cpp
+++ b/src/fdcache.cpp
@@ -34,20 +34,6 @@
 #include "string_util.h"
 #include "autolock.h"
 
-//------------------------------------------------
-// Symbols
-//------------------------------------------------
-#define TMPFILE_FOR_CHECK_HOLE  "/tmp/.s3fs_hole_check.tmp"
-
-//
-// For cache directory top path
-//
-#if defined(P_tmpdir)
-#define TMPFILE_DIR_0PATH   P_tmpdir
-#else
-#define TMPFILE_DIR_0PATH   "/tmp"
-#endif
-
 //
 // The following symbols are used by FdManager::RawCheckAllCache().
 //
@@ -99,6 +85,7 @@ off_t           FdManager::free_disk_space = 0;
 std::string     FdManager::check_cache_output;
 bool            FdManager::checked_lseek(false);
 bool            FdManager::have_lseek_hole(false);
+std::string     FdManager::tmp_dir = "/tmp";
 
 //------------------------------------------------
 // FdManager class methods
@@ -250,17 +237,7 @@ bool FdManager::CheckCacheDirExist()
     if(FdManager::cache_dir.empty()){
         return true;
     }
-    // check the directory
-    struct stat st;
-    if(0 != stat(cache_dir.c_str(), &st)){
-        S3FS_PRN_ERR("could not access to cache directory(%s) by errno(%d).", cache_dir.c_str(), errno);
-        return false;
-    }
-    if(!S_ISDIR(st.st_mode)){
-        S3FS_PRN_ERR("the cache directory(%s) is not directory.", cache_dir.c_str());
-        return false;
-    }
-    return true;
+    return IsDir(&cache_dir);
 }
 
 off_t FdManager::GetEnsureFreeDiskSpace()
@@ -288,7 +265,7 @@ off_t FdManager::GetFreeDiskSpace(const char* path)
             ctoppath += "/";
         }
     }else{
-        ctoppath = TMPFILE_DIR_0PATH "/";
+        ctoppath = tmp_dir + "/";
     }
     if(path && '\0' != *path){
         ctoppath += path;
@@ -314,10 +291,14 @@ bool FdManager::HaveLseekHole()
         return FdManager::have_lseek_hole;
     }
 
-    // create tempolary file
-    int fd;
-    if(-1 == (fd = open(TMPFILE_FOR_CHECK_HOLE, O_CREAT|O_RDWR, 0600))){
-        S3FS_PRN_ERR("failed to open tempolary file(%s) - errno(%d)", TMPFILE_FOR_CHECK_HOLE, errno);
+    // create temporary file
+    FILE* ptmpfp;
+    int   fd;
+    if(NULL == (ptmpfp = MakeTempFile()) || -1 == (fd = fileno(ptmpfp))){
+        S3FS_PRN_ERR("failed to open temporary file by errno(%d)", errno);
+        if(ptmpfp){
+            fclose(ptmpfp);
+        }
         FdManager::checked_lseek   = true;
         FdManager::have_lseek_hole = false;
         return FdManager::have_lseek_hole;
@@ -338,13 +319,64 @@ bool FdManager::HaveLseekHole()
         }
     }
     close(fd);
-    unlink(TMPFILE_FOR_CHECK_HOLE);
 
     FdManager::checked_lseek   = true;
     FdManager::have_lseek_hole = result;
     return FdManager::have_lseek_hole;
 }
 
+bool FdManager::SetTmpDir(const char *dir)
+{
+    if(!dir || '\0' == dir[0]){
+        tmp_dir = "/tmp";
+    }else{
+        tmp_dir = dir;
+    }
+    return true;
+}
+
+bool FdManager::IsDir(const std::string* dir)
+{
+    // check the directory
+    struct stat st;
+    if(0 != stat(dir->c_str(), &st)){
+        S3FS_PRN_ERR("could not stat() directory %s by errno(%d).", dir->c_str(), errno);
+        return false;
+    }
+    if(!S_ISDIR(st.st_mode)){
+        S3FS_PRN_ERR("the directory %s is not a directory.", dir->c_str());
+        return false;
+    }
+    return true;
+}
+
+bool FdManager::CheckTmpDirExist()
+{
+    if(FdManager::tmp_dir.empty()){
+        return true;
+    }
+    return IsDir(&tmp_dir);
+}
+
+FILE* FdManager::MakeTempFile() {
+    int fd;
+    char cfn[PATH_MAX];
+    std::string fn = tmp_dir + "/s3fstmp.XXXXXX";
+    strncpy(cfn, fn.c_str(), sizeof(cfn) - 1);
+    cfn[sizeof(cfn) - 1] = '\0';
+
+    fd = mkstemp(cfn);
+    if (-1 == fd) {
+        S3FS_PRN_ERR("failed to create tmp file. errno(%d)", errno);
+        return NULL;
+    }
+    if (-1 == unlink(cfn)) {
+        S3FS_PRN_ERR("failed to delete tmp file. errno(%d)", errno);
+        return NULL;
+    }
+    return fdopen(fd, "rb+");
+}
+
 bool FdManager::HasOpenEntityFd(const char* path)
 {
     AutoLock auto_lock(&FdManager::fd_manager_lock);
diff --git a/src/fdcache.h b/src/fdcache.h
index 7393556..a5adbd1 100644
--- a/src/fdcache.h
+++ b/src/fdcache.h
@@ -40,6 +40,7 @@ class FdManager
       static std::string     check_cache_output;
       static bool            checked_lseek;
       static bool            have_lseek_hole;
+      static std::string     tmp_dir;
 
       fdent_map_t            fent;
 
@@ -47,6 +48,7 @@ class FdManager
       static off_t GetFreeDiskSpace(const char* path);
       void CleanupCacheDirInternal(const std::string &path = "");
       bool RawCheckAllCache(FILE* fp, const char* cache_stat_top_dir, const char* sub_path, int& total_file_cnt, int& err_file_cnt, int& err_dir_cnt);
+      static bool IsDir(const std::string* dir);
 
   public:
       FdManager();
@@ -74,6 +76,9 @@ class FdManager
       static void FreeReservedDiskSpace(off_t size);
       static bool ReserveDiskSpace(off_t size);
       static bool HaveLseekHole();
+      static bool SetTmpDir(const char* dir);
+      static bool CheckTmpDirExist();
+      static FILE* MakeTempFile();
 
       // Return FdEntity associated with path, returning NULL on error.  This operation increments the reference count; callers must decrement via Close after use.
       FdEntity* GetFdEntity(const char* path, int& existfd, bool newfd = true, bool lock_already_held = false);
diff --git a/src/fdcache_entity.cpp b/src/fdcache_entity.cpp
index 4c5150f..38ac1c3 100644
--- a/src/fdcache_entity.cpp
+++ b/src/fdcache_entity.cpp
@@ -562,8 +562,8 @@ int FdEntity::Open(headers_t* pmeta, off_t size, time_t time, int flags, AutoLoc
             inode = 0;
 
             // open temporary file
-            if(NULL == (pfile = tmpfile()) || -1 ==(physical_fd = fileno(pfile))){
-                S3FS_PRN_ERR("failed to open tmp file. err(%d)", errno);
+            if(NULL == (pfile = FdManager::MakeTempFile()) || -1 ==(physical_fd = fileno(pfile))){
+                S3FS_PRN_ERR("failed to open temporary file by errno(%d)", errno);
                 if(pfile){
                     fclose(pfile);
                     pfile = NULL;
@@ -1088,8 +1088,8 @@ int FdEntity::NoCacheLoadAndPost(PseudoFdInfo* pseudo_obj, off_t start, off_t si
     // open temporary file
     FILE* ptmpfp;
     int   tmpfd;
-    if(NULL == (ptmpfp = tmpfile()) || -1 ==(tmpfd = fileno(ptmpfp))){
-        S3FS_PRN_ERR("failed to open tmp file. err(%d)", errno);
+    if(NULL == (ptmpfp = FdManager::MakeTempFile()) || -1 ==(tmpfd = fileno(ptmpfp))){
+        S3FS_PRN_ERR("failed to open temporary file by errno(%d)", errno);
         if(ptmpfp){
             fclose(ptmpfp);
         }
diff --git a/src/s3fs.cpp b/src/s3fs.cpp
index 8faa5a9..c3678ec 100644
--- a/src/s3fs.cpp
+++ b/src/s3fs.cpp
@@ -4250,6 +4250,10 @@ static int my_fuse_opt_proc(void* data, const char* arg, int key, struct fuse_ar
             S3fsCurl::SetRetries(static_cast<int>(retries));
             return 0;
         }
+        if(is_prefix(arg, "tmpdir=")){
+            FdManager::SetTmpDir(strchr(arg, '=') + sizeof(char));
+            return 0;
+        }
         if(is_prefix(arg, "use_cache=")){
             FdManager::SetCacheDir(strchr(arg, '=') + sizeof(char));
             return 0;
@@ -5099,6 +5103,14 @@ int main(int argc, char* argv[])
         // like checking for appropriate lengths and characters  
     }
 
+    // check tmp dir permission
+    if(!FdManager::CheckTmpDirExist()){
+        S3FS_PRN_EXIT("temporary directory doesn't exists.");
+        S3fsCurl::DestroyS3fsCurl();
+        s3fs_destroy_global_ssl();
+        exit(EXIT_FAILURE);
+    }
+
     // check cache dir permission
     if(!FdManager::CheckCacheDirExist() || !FdManager::CheckCacheTopDir() || !CacheFileStat::CheckCacheFileStatTopDir()){
         S3FS_PRN_EXIT("could not allow cache directory permission, check permission of cache directories.");
diff --git a/src/s3fs_help.cpp b/src/s3fs_help.cpp
index 01ca1de..757f4e4 100644
--- a/src/s3fs_help.cpp
+++ b/src/s3fs_help.cpp
@@ -70,6 +70,9 @@ static const char help_string[] =
     "   retries (default=\"5\")\n"
     "      - number of times to retry a failed S3 transaction\n"
     "\n"
+    "   tmpdir (default=\"/tmp\")\n"
+    "      - local folder for temporary files.\n"
+    "\n"
     "   use_cache (default=\"\" which means disabled)\n"
     "      - local folder to use for local file cache\n"
     "\n"