files: move smtp prune logic to main

Now that we call the file prune loop very regularly, we can move the
SMTP specific inspection pruning logic into this loop. Helps with
cases there we don't (often) update a files inspection trackers.

src/app-layer-smtp.c

@@ -368,41 +368,6 @@ static SMTPTransaction *SMTPTransactionCreate(void)
     return tx;
 }
 
-/** \internal
- *  \brief update inspected tracker if it gets to far behind
- *
- *  As smtp uses the FILE_USE_DETECT flag in the file API, we are responsible
- *  for making sure that File::content_inspected is not getting too far
- *  behind.
- */
-static void SMTPPruneFiles(FileContainer *files)
-{
-    SCLogDebug("cfg: win %"PRIu32" min_size %"PRIu32,
-            smtp_config.content_inspect_window, smtp_config.content_inspect_min_size);
-
-    File *file = files->head;
-    while (file) {
-        SCLogDebug("file %p", file);
-        uint32_t window = smtp_config.content_inspect_window;
-        if (file->sb->stream_offset == 0)
-            window = MAX(window, smtp_config.content_inspect_min_size);
-
-        uint64_t file_size = FileDataSize(file);
-        uint64_t data_size = file_size - file->sb->stream_offset;
-
-        SCLogDebug("window %"PRIu32", file_size %"PRIu64", data_size %"PRIu64,
-                window, file_size, data_size);
-
-        if (data_size > (window * 3)) {
-            uint64_t left_edge = file_size - window;
-            SCLogDebug("file->content_inspected now %"PRIu64, left_edge);
-            file->content_inspected = left_edge;
-        }
-
-        file = file->next;
-    }
-}
-
 static void FlagDetectStateNewFile(SMTPTransaction *tx)
 {
     if (tx && tx->de_state) {
@@ -473,6 +438,8 @@ int SMTPProcessDataChunk(const uint8_t *chunk, uint32_t len,
                 SCLogDebug("FileOpenFile() failed");
             }
             FlagDetectStateNewFile(smtp_state->curr_tx);
+            files->tail->inspect_window = smtp_config.content_inspect_window;
+            files->tail->inspect_min_size = smtp_config.content_inspect_min_size;
 
             /* If close in the same chunk, then pass in empty bytes */
             if (state->body_end) {
@@ -562,11 +529,6 @@ int SMTPProcessDataChunk(const uint8_t *chunk, uint32_t len,
     } else {
         SCLogDebug("Body not a Ctnt_attachment");
     }
-
-    if (files != NULL) {
-        SMTPPruneFiles(files);
-    }
-
     SCReturnInt(ret);
 }
 

src/util-file.c

@@ -319,6 +319,26 @@ static int FilePruneFile(File *file)
     }
     if (file->flags & FILE_USE_DETECT) {
         left_edge = MIN(left_edge, file->content_inspected);
+
+        /* if file has inspect window and min size set, we
+         * do some house keeping here */
+        if (file->inspect_window != 0 && file->inspect_min_size != 0) {
+            uint32_t window = file->inspect_window;
+            if (file->sb->stream_offset == 0)
+                window = MAX(window, file->inspect_min_size);
+
+            uint64_t file_size = FileDataSize(file);
+            uint64_t data_size = file_size - file->sb->stream_offset;
+
+            SCLogDebug("window %"PRIu32", file_size %"PRIu64", data_size %"PRIu64,
+                    window, file_size, data_size);
+
+            if (data_size > (window * 3)) {
+                left_edge = file_size - window;
+                SCLogDebug("file->content_inspected now %"PRIu64, left_edge);
+                file->content_inspected = left_edge;
+            }
+        }
     }
 
     if (left_edge) {

src/util-file.h

@@ -87,6 +87,8 @@ typedef struct File_ {
                                      *   flag is set */
     uint64_t content_stored;
     uint64_t size;
+    uint32_t inspect_window;
+    uint32_t inspect_min_size;
     uint64_t start;
     uint64_t end;