add nn.find

README.md

@@ -1,10 +1,5 @@
-# Building stuff in containers
+# "nn.find" (similar to `find`)
 
-## Rationale / sought for Benefits
-
-1. "cleanliness", all dependencies can be setup / installed in container and do not needlessly remain after build
-2. "less/no missing dependecies"
-3. "hightened" reproducibility
 
 ## Usage:
 

source/Makefile

@@ -1,2 +1,2 @@
-all:
-	echo hallo 
+find: find.c
+	gcc "$<" -o "$@"

source/find.c

@@ -0,0 +1,140 @@
+#include <errno.h>
+#include <sys/types.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+// strlen
+#include <string.h>
+// malloc
+#include <stdlib.h>
+//DIR *opendir(const char *name);
+//DIR *fdopendir(int fd);
+//int fstatat(int dirfd, const char *pathname, struct stat *buf,
+//            int flags);
+
+
+int list(int dirfd, char* curdir,int length){
+    char* next_curdirnext = NULL;
+    int next_length = 0;
+//    putchar
+    
+    DIR* pdir = fdopendir(dirfd);
+    if(pdir==NULL){
+        perror("fehler fopendir");
+        return 1;
+    }   
+    struct dirent * pdirent = NULL;  
+    struct stat statbuf;
+    while(1)
+    {
+        errno = 0; 
+        pdirent = readdir(pdir);
+        if(pdirent==NULL){
+            if(errno==0)
+            {
+//                printf("end reached\n");
+                closedir(pdir);        
+                break;
+            }
+            else
+            {
+                fprintf(stderr," readdir errno = %d\n",errno);
+                return 1; 
+            }
+        }
+        else
+        {
+            if(pdirent->d_name[0]=='.'){
+                if(pdirent->d_name[1]==0){
+                    //printf("ignore SELF\n");
+                    continue;
+                }
+                if(pdirent->d_name[1]=='.'){
+                    if(pdirent->d_name[2]==0){
+                     //   printf("ignore PARENT\n");
+                        continue;
+                    }
+                }
+            }
+            if( 0== fstatat(dirfd,pdirent->d_name,&statbuf,AT_SYMLINK_NOFOLLOW) )
+            {
+                printf("%s/%s\n",curdir,pdirent->d_name);
+                if(S_ISDIR(statbuf.st_mode)){
+               //     printf("%s\n",pdirent->d_name);
+                    int subdirfd = openat(dirfd,pdirent->d_name,O_RDONLY); 
+                    if(-1 == subdirfd)
+                    {
+                        perror("subdirfd");
+                    } else {
+                        next_length=(length+1+strlen(pdirent->d_name));
+                        next_curdirnext = malloc(next_length);
+                        if(next_curdirnext==NULL)
+                        {
+                            perror("malloc");
+                        } 
+                        else 
+                        {
+                            sprintf(next_curdirnext,"%s/%s",curdir,pdirent->d_name);
+                            list(subdirfd,next_curdirnext,next_length);
+                            free(next_curdirnext);
+                            close(subdirfd);
+                        }
+                    }
+                } 
+                //else
+                //{
+                ////    printf("%s/%s\n",curdir,pdirent->d_name);
+                //}
+                   //struct stat {
+                   //    dev_t      st_dev;      /* ID of device containing file */
+                   //    ino_t      st_ino;      /* Inode number */
+                   //    mode_t     st_mode;     /* File type and mode */
+                   //    nlink_t    st_nlink;    /* Number of hard links */
+                   //    uid_t      st_uid;      /* User ID of owner */
+                   //    gid_t      st_gid;      /* Group ID of owner */
+                   //    dev_t      st_rdev;     /* Device ID (if special file) */
+                   //    off_t      st_size;     /* Total size, in bytes */
+                   //    blksize_t  st_blksize;  /* Block size for filesystem I/O */
+                   //    blkcnt_t   st_blocks;   /* Number of 512 B blocks allocated */
+
+                   //    /* Since POSIX.1-2008, this structure supports nanosecond
+                   //       precision for the following timestamp fields.
+                   //       For the details before POSIX.1-2008, see VERSIONS. */
+
+                   //    struct timespec  st_atim;  /* Time of last access */
+                   //    struct timespec  st_mtim;  /* Time of last modification */
+                   //    struct timespec  st_ctim;  /* Time of last status change */
+
+                   //#define st_atime  st_atim.tv_sec  /* Backward compatibility */
+                   //#define st_mtime  st_mtim.tv_sec
+                   //#define st_ctime  st_ctim.tv_sec
+                   //}; 
+            }
+            else
+            {
+                fprintf(stderr,"fstatat errno = %d\n",errno);
+                return 2; 
+            }
+            //printf("%d %s\n",pdirent->d_type ,pdirent->d_name);
+        }
+    } 
+//    printf("dirfd = %d %p\n",dirfd,pdir);
+    return 0;
+}
+
+
+int main(int argc, char* argv[]){
+//    DIR current;
+    int dirfd;
+    char* curdir= "."; 
+    puts(".");
+    dirfd = openat(AT_FDCWD,".",O_RDONLY); 
+    if (dirfd > -1){
+        list(dirfd,curdir,1+strlen(curdir));
+    }
+    return 0;
+}
+
+