sysrap/tests/mkdirp.cc

0001 // name=mkdirp ; gcc $name.cc -std=c++11 -lstdc++ -o /tmp/$name && /tmp/$name
0002 // https://stackoverflow.com/questions/675039/how-can-i-create-directory-tree-in-c-linux
0003
0004 #include <cstring>
0005 #include <cstdlib>
0006 #include <cstdio>
0007 #include <sys/stat.h>
0008 #include <errno.h>
0009
0010 /**
0011 //                        0700      040        010       04        01
0012
0013 In [13]: print(oct(0o700 | 0o40 | 0o10 | 0o4 | 0o01))
0014 0o755
0015
0016 **/
0017
0018 int mkdirp(const char* path, int mode_ = 0  );
0019
0020
0021 int mkdirp(const char* path_, int mode_ )
0022 {
0023     mode_t default_mode = S_IRWXU | S_IRGRP |  S_IXGRP | S_IROTH | S_IXOTH ;
0024     mode_t mode = mode_ == 0 ? default_mode : mode_ ;
0025
0026     char* path = strdup(path_);
0027     char* p = path ;
0028     int rc = 0 ;
0029
0030     while (*p != '\0' && rc == 0)
0031     {
0032         p++;                                 // advance past leading character, probably slash, and subsequent slashes the next line gets to
0033         while(*p != '\0' && *p != '/') p++;  // advance p until subsequent slash
0034         char v = *p;                         // store the slash
0035         *p = '\0' ;                          // replace slash with string terminator
0036         printf("%s\n", path );
0037         rc = mkdir(path, mode) == -1 && errno != EEXIST ? 1 : 0 ;  // set rc non-zero for mkdir errors other than exists already
0038         *p = v;                              // put back the slash
0039     }
0040     free(path);
0041     return rc ;
0042 }
0043
0044 int main(int argc, char** argv)
0045 {
0046     const char* path = "/tmp/red/green/blue" ;
0047     int mode = 0777 ;
0048     int rc = mkdirp(path, mode);
0049     return rc ;
0050 }
0051
0052
0053