mkdir_p: purge from codebase, use std::filesystem. (#2571)

This should remove some of our code smells, too, while simplifying
things.

src/coreneuron/apps/main1.cpp

@@ -15,6 +15,7 @@
 #include <cstring>
 #include <climits>
 #include <dlfcn.h>
+#include <filesystem>
 #include <memory>
 #include <vector>
 
@@ -40,11 +41,12 @@
 #include "coreneuron/network/partrans.hpp"
 #include "coreneuron/network/multisend.hpp"
 #include "coreneuron/io/nrn_setup.hpp"
-#include "coreneuron/io/file_utils.hpp"
 #include "coreneuron/io/nrn2core_direct.h"
 #include "coreneuron/io/core2nrn_data_return.hpp"
 #include "coreneuron/utils/utils.hpp"
 
+namespace fs = std::filesystem;
+
 extern "C" {
 const char* corenrn_version() {
     return coreneuron::bbcore_write_version;
@@ -501,7 +503,7 @@ extern "C" int run_solve_core(int argc, char** argv) {
 
     // Create outpath if it does not exist
     if (nrnmpi_myid == 0) {
-        mkdir_p(corenrn_param.outpath.c_str());
+        fs::create_directories(corenrn_param.outpath);
     }
 
     if (!corenrn_param.reportfilepath.empty()) {
@@ -522,7 +524,7 @@ extern "C" int run_solve_core(int argc, char** argv) {
     std::string output_dir = corenrn_param.outpath;
 
     if (nrnmpi_myid == 0) {
-        mkdir_p(output_dir.c_str());
+        fs::create_directories(output_dir);
     }
 #if NRNMPI
     if (corenrn_param.mpi_enable) {

src/coreneuron/io/nrn_checkpoint.cpp

@@ -5,6 +5,7 @@
 # See top-level LICENSE file for details.
 # =============================================================================.
 */
+#include <filesystem>
 #include <iostream>
 #include <sstream>
 #include <cassert>
@@ -19,13 +20,14 @@
 #include "coreneuron/network/netpar.hpp"
 #include "coreneuron/utils/vrecitem.h"
 #include "coreneuron/mechanism/mech/mod2c_core_thread.hpp"
-#include "coreneuron/io/file_utils.hpp"
 #include "coreneuron/permute/data_layout.hpp"
 #include "coreneuron/permute/node_permute.h"
 #include "coreneuron/coreneuron.hpp"
 #include "coreneuron/utils/nrnoc_aux.hpp"
 #include "coreneuron/apps/corenrn_parameters.hpp"
 
+namespace fs = std::filesystem;
+
 namespace coreneuron {
 // Those functions comes from mod file directly
 extern int checkpoint_save_patternstim(_threadargsproto_);
@@ -37,7 +39,7 @@ CheckPoints::CheckPoints(const std::string& save, const std::string& restore)
     , restored(false) {
     if (!save.empty()) {
         if (nrnmpi_myid == 0) {
-            mkdir_p(save.c_str());
+            fs::create_directories(save);
         }
     }
 }

src/nmodl/io.cpp

@@ -445,49 +445,3 @@ static int file_stack_empty() {
     }
     return (filestack->next == filestack);
 }
-
-/* adapted from : gist@jonathonreinhart/mkdir_p.c */
-int mkdir_p(const char* path) {
-    const size_t len = strlen(path);
-    char mypath[PATH_MAX];
-    char* p;
-
-    errno = 0;
-
-    /* copy string so its mutable */
-    if (len > sizeof(mypath) - 1) {
-        fprintf(stderr, "Output directory path too long\n");
-        return -1;
-    }
-
-    strcpy(mypath, path);
-
-    /* iterate the string */
-    for (p = mypath + 1; *p; p++) {
-        if (*p == '/') {
-            /* temporarily truncate */
-            *p = '\0';
-
-#if defined(_WIN32)
-            if (_mkdir(mypath) != 0) {
-#else
-            if (mkdir(mypath, S_IRWXU) != 0) {
-#endif
-                if (errno != EEXIST)
-                    return -1;
-            }
-            *p = '/';
-        }
-    }
-
-#if defined(_WIN32)
-    if (_mkdir(mypath) != 0) {
-#else
-    if (mkdir(mypath, S_IRWXU) != 0) {
-#endif
-        if (errno != EEXIST)
-            return -1;
-    }
-
-    return 0;
-}

src/nmodl/modl.cpp

@@ -34,6 +34,9 @@
 #include "modl.h"
 
 #include <cstring>
+#include <filesystem>
+
+namespace fs = std::filesystem;
 
 FILE *fin,    /* input file descriptor for filename.mod */
               /* or file2 from the second argument */
@@ -55,7 +58,6 @@ int nmodl_text = 1;
 List* filetxtlist;
 
 extern int yyparse();
-extern int mkdir_p(const char*);
 
 extern int vectorize;
 extern int numlist;
@@ -276,7 +278,9 @@ static void openfiles(char* given_filename, char* output_dir) {
         }
     }
     if (output_dir) {
-        if (mkdir_p(output_dir) != 0) {
+        try {
+            fs::create_directories(output_dir);
+        } catch (...) {
             fprintf(stderr, "Can't create output directory %s\n", output_dir);
             exit(1);
         }