Modifying zfsaddhomedir to operate on not-zfs stuff. Ignores quotas and ACLs.

src/simpleaddhomedir.c

@@ -0,0 +1,137 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <assert.h>
+#include "util.h"
+
+int main(int argc, char *argv[]) {
+    if(argc < 7) {
+        fprintf(stderr, "Usage: simpleaddhomedir homedir skeldir uid gid mode\n");
+        return 1;
+    }
+
+    char *homedir = argv[1];
+    char *skeldir = argv[2];
+    char *mode = argv[5];
+    uid_t uid, gid;
+    char *zfs_bin = "/usr/sbin/zfs";
+    char *mkdir_bin = "/bin/mkdir";
+    char *chmod_bin = "/bin/chmod";
+    char *dataset = homedir + 1;
+    char *create_argv[] = { "mkdir", dataset, NULL };
+    char *mode_argv[] = { "chmod", mode, homedir, NULL };
+    DIR *skel;
+    struct dirent *skelent;
+
+    assert(homedir[0]);
+    uid = atol(argv[3]);
+    gid = atol(argv[4]);
+
+    if(spawnv(mkdir_bin, create_argv))
+        return 1;
+    //Quotas are ignored now, or so I'm told.
+    /* if(spawnv(zfs_bin, quota_argv)) */
+    /*     return 1; */
+    if(spawnv(chmod_bin, mode_argv))
+        return 1;
+    //Fuck ACLs.  The instructions I got didn't include them.
+    /* if(acl && spawnv(chmod_bin, acl_argv)) */
+    /*     return 1; */
+
+    skel = opendir(skeldir);
+    if (!skel) {
+        errorpe("failed to open %s", skeldir);
+        return -1;
+    }
+
+    while ((skelent = readdir(skel))) {
+        struct stat sb;
+        char src[PATH_MAX], dest[PATH_MAX];
+
+        if (!strcmp(skelent->d_name, ".") || !strcmp(skelent->d_name, ".."))
+            continue;
+
+        snprintf(src, sizeof(src), "%s/%s", skeldir, skelent->d_name);
+        snprintf(dest, sizeof(dest), "/%s/%s", homedir, skelent->d_name);
+        lstat(src, &sb);
+
+        if (sb.st_uid || sb.st_gid) {
+            warn("not creating %s due to ownership", dest);
+            continue;
+        }
+
+        if (S_ISREG(sb.st_mode)) {
+            int bytes;
+            char buf[4096];
+
+            int srcfd = open(src, O_RDONLY);
+            if (srcfd == -1) {
+                warnpe("open: %s", src);
+                continue;
+            }
+
+            int destfd = open(dest, O_WRONLY|O_CREAT|O_EXCL, sb.st_mode & 0777);
+            if (destfd == -1) {
+                warnpe("open: %s", dest);
+                close(srcfd);
+                continue;
+            }
+
+            for (;;) {
+                bytes = read(srcfd, buf, sizeof(buf));
+                if (!bytes)
+                    break;
+                if (bytes < 0) {
+                    warnpe("read");
+                    break;
+                }
+                if (write(destfd, buf, bytes) < 0) {
+                    warnpe("write");
+                    break;
+                }
+            }
+            if (fchown(destfd, uid, gid))
+                errorpe("chown: %s", dest);
+
+            close(srcfd);
+            close(destfd);
+        } else if (S_ISDIR(sb.st_mode)) {
+            if (mkdir(dest, sb.st_mode & 0777)) {
+                warnpe("mkdir: %s", dest);
+                continue;
+            }
+            if (chown(dest, uid, gid))
+                errorpe("chown: %s", dest);
+        } else if (S_ISLNK(sb.st_mode)) {
+            char lnkdest[PATH_MAX];
+            int bytes;
+            bytes = readlink(src, lnkdest, sizeof(lnkdest));
+            lnkdest[bytes] = '\0';
+            if (bytes == -1) {
+                warnpe("readlink: %s", src);
+                continue;
+            }
+            if (symlink(lnkdest, dest)) {
+                warnpe("symlink: %s", dest);
+                continue;
+            }
+            if (lchown(dest, uid, gid))
+                errorpe("lchown: %s", dest);
+        } else {
+            warn("not creating %s", dest);
+        }
+    }
+
+    closedir(skel);
+
+    if (chown(homedir, uid, gid)) {
+        errorpe("failed to chown %s", homedir);
+        return -1;
+    }
+
+    return 0;
+}