gufi_query descend fallback to calling lstat if d_type was not set

Author: calccrypto

include/descend.h

@@ -84,6 +84,8 @@ struct descend_counters {
     size_t external_dbs;
 };
 
+struct work *try_skip_lstat(const unsigned char d_type, struct work *work);
+
 /*
  * Push the subdirectories in the current directory onto the queue
  * and process non directories using a user provided function

include/gufi_query/gqw.h

@@ -89,7 +89,7 @@ size_t gqw_size(gqw_t *gqw);
 /* allocate a gqw and fill in some fields */
 gqw_t *new_gqw_with_name(const char *prefix, const size_t prefix_len,
                          const char *basename, const size_t basename_len,
-                         int *isdir, const int next_level,
+                         const unsigned char d_type, const int next_level,
                          const char *sqlite3_prefix, const size_t sqlite3_prefix_len);
 
 /* call compress_struct to compress a gqw, but call this to decompress */

src/descend.c

@@ -80,6 +80,39 @@ static int work_serialize_and_free(const int fd, QPTPool_f func, void *work, siz
 }
 #endif
 
+struct work *try_skip_lstat(const unsigned char d_type, struct work *work) {
+    switch (d_type) {
+        case DT_DIR:
+            work->statuso.st_mode = S_IFDIR;
+            break;
+        case DT_LNK:
+            work->statuso.st_mode = S_IFLNK;
+            break;
+        case DT_REG:
+            work->statuso.st_mode = S_IFREG;
+            break;
+        case DT_FIFO:
+        case DT_SOCK:
+        case DT_CHR:
+        case DT_BLK:
+            break;
+        case DT_UNKNOWN:
+        default:
+            /* some filesystems don't support d_type - fall back to calling lstat */
+            if (lstat(work->name, &work->statuso) != 0) {
+                const int err = errno;
+                fprintf(stderr, "Error: Could not stat \"%s\": %s (%d)\n",
+                        work->name, strerror(err), err);
+                return NULL;
+            }
+
+            work->lstat_called = 1;
+            break;
+    }
+
+    return work;
+}
+
 /*
  * Push the subdirectories in the current directory onto the queue
  * and process non directories using a user provided function.
@@ -141,30 +174,8 @@ int descend(QPTPool_t *ctx, const size_t id, void *args,
             child->root_parent = work->root_parent;
             child->pinode = inode;
 
-            switch (dir_child->d_type) {
-                case DT_DIR:
-                    child->statuso.st_mode = S_IFDIR;
-                    break;
-                case DT_LNK:
-                    child->statuso.st_mode = S_IFLNK;
-                    break;
-                case DT_REG:
-                    child->statuso.st_mode = S_IFREG;
-                    break;
-                case DT_FIFO:
-                case DT_SOCK:
-                case DT_CHR:
-                case DT_BLK:
-                    break;
-                case DT_UNKNOWN:
-                default:
-                    /* some filesystems don't support d_type - fall back to calling lstat */
-                    if (lstat(child->name, &child->statuso) != 0) {
-                        continue;
-                    }
-
-                    child->lstat_called = 1;
-                    break;
+            if (!try_skip_lstat(dir_child->d_type, child)) {
+                continue;
             }
 
             /* push subdirectories onto the queue */

src/gufi_query/gqw.c

@@ -62,10 +62,13 @@ OF SUCH DAMAGE.
 
 
 
+#include <errno.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include "descend.h"
 #include "dbutils.h"
 #include "gufi_query/gqw.h"
 #include "utils.h"
@@ -86,7 +89,7 @@ size_t gqw_size(gqw_t *gqw) {
  */
 gqw_t *new_gqw_with_name(const char *prefix, const size_t prefix_len,
                          const char *basename, const size_t basename_len,
-                         int *isdir, const int next_level,
+                         const unsigned char d_type, const int next_level,
                          const char *sqlite3_prefix, const size_t sqlite3_prefix_len) {
     /* +1 for path separator */
     const size_t name_len = prefix_len + 1 + basename_len;
@@ -102,18 +105,26 @@ gqw_t *new_gqw_with_name(const char *prefix, const size_t prefix_len,
                                     "/", (size_t) 1,
                                     basename, basename_len);
 
-    if (!*isdir) {
-        /* allow for paths immediately under the input paths to be symlinks */
-        if (next_level < 2) {
-            struct stat st;
-            if (stat(gqw->work.name, &st) == 0) {
-                *isdir = S_ISDIR(st.st_mode);
-            }
-            /* errors are ignored */
+    /* allow for paths immediately under the input paths to be symlinks */
+    if (next_level < 2) {
+        if (stat(gqw->work.name, &gqw->work.statuso) != 0) {
+            const int err = errno;
+            fprintf(stderr, "Error: Could not stat \"%s\": %s (%d)\n",
+                    gqw->work.name, strerror(err), err);
+            free(gqw);
+            return NULL;
+        }
+
+        gqw->work.lstat_called = 1;
+    }
+    else {
+        if (!try_skip_lstat(d_type, &gqw->work)) {
+            free(gqw);
+            return NULL;
         }
     }
 
-    if (*isdir) {
+    if (S_ISDIR(gqw->work.statuso.st_mode)) {
         gqw->sqlite3_name = gqw->work.name + name_len + 1;
 
         /* append converted entry name to converted directory */

src/gufi_query/process_queries.c

@@ -110,13 +110,15 @@ static size_t descend2(QPTPool_t *ctx,
                 continue;
             }
 
-            int isdir = (entry->d_type == DT_DIR);
             gqw_t *child = new_gqw_with_name(gqw->work.name, gqw->work.name_len,
                                              entry->d_name, len,
-                                             &isdir, next_level,
+                                             entry->d_type, next_level,
                                              gqw->sqlite3_name, gqw->sqlite3_name_len);
+            if (!child) {
+                continue;
+            }
 
-            if (isdir) {
+            if (S_ISDIR(child->work.statuso.st_mode)) {
                 if (subdir_within_range(in, next_level, entry->d_name, len) != 1) {
                     free(child);
                     continue;