Rework fullscrape worker, unifying non-gzip and gzip code was a bad idea

1 files changed, 158 insertions, 125 deletions

diff --git a/ot_fullscrape.c b/ot_fullscrape.c
index faea4b9..e7a1c19 100644
--- a/ot_fullscrape.c
+++ b/ot_fullscrape.c
@@ -35,16 +35,11 @@
 /* "d8:completei%zde10:downloadedi%zde10:incompletei%zdee" */
 #define OT_SCRAPE_MAXENTRYLEN 256
 
-#ifdef WANT_COMPRESSION_GZIP
-#define IF_COMPRESSION( TASK ) if( mode & TASK_FLAG_GZIP ) TASK
-#define WANT_COMPRESSION_GZIP_PARAM( param1, param2, param3 ) , param1, param2, param3
-#else
-#define IF_COMPRESSION( TASK )
-#define WANT_COMPRESSION_GZIP_PARAM( param1, param2, param3 )
-#endif
-
 /* Forward declaration */
 static void fullscrape_make( int *iovec_entries, struct iovec **iovector, ot_tasktype mode );
+#ifdef WANT_COMPRESSION_GZIP
+static void fullscrape_make_gzip( int *iovec_entries, struct iovec **iovector, ot_tasktype mode );
+#endif
 
 /* Converter function from memory to human readable hex strings
    XXX - Duplicated from ot_stats. Needs fix. */
@@ -59,14 +54,17 @@ static void * fullscrape_worker( void * args ) {
 
   (void) args;
 
-  while( 1 ) {
+  while( g_opentracker_running ) {
     ot_tasktype tasktype = TASK_FULLSCRAPE;
     ot_taskid   taskid   = mutex_workqueue_poptask( &tasktype );
-    fullscrape_make( &iovec_entries, &iovector, tasktype );
+#ifdef WANT_COMPRESSION_GZIP
+    if (tasktype & TASK_FLAG_GZIP)
+        fullscrape_make_gzip( &iovec_entries, &iovector, tasktype );
+    else
+#endif
+        fullscrape_make( &iovec_entries, &iovector, tasktype );
     if( mutex_workqueue_pushresult( taskid, iovec_entries, iovector ) )
       iovec_free( &iovec_entries, &iovector );
-    if( !g_opentracker_running )
-      return NULL;
   }
   return NULL;
 }
@@ -84,68 +82,57 @@ void fullscrape_deliver( int64 sock, ot_tasktype tasktype ) {
   mutex_workqueue_pushtask( sock, tasktype );
 }
 
-static int fullscrape_increase( int *iovec_entries, struct iovec **iovector,
-                         char **r, char **re  WANT_COMPRESSION_GZIP_PARAM( z_stream *strm, ot_tasktype mode, int zaction ) ) {
-  /* Allocate a fresh output buffer at the end of our buffers list */
-  if( !( *r = iovec_fix_increase_or_free( iovec_entries, iovector, *r, OT_SCRAPE_CHUNK_SIZE ) ) ) {
-
-    /* Deallocate gzip buffers */
-    IF_COMPRESSION( deflateEnd(strm); )
-
-    /* Release lock on current bucket and return */
-    return -1;
-  }
-
-  /* Adjust new end of output buffer */
-  *re = *r + OT_SCRAPE_CHUNK_SIZE - OT_SCRAPE_MAXENTRYLEN;
-
-  /* When compressing, we have all the bytes in output buffer */
-#ifdef WANT_COMPRESSION_GZIP
-  if( mode & TASK_FLAG_GZIP ) {
-    int zres;
-    *re -= OT_SCRAPE_MAXENTRYLEN;
-    strm->next_out  = (uint8_t*)*r;
-    strm->avail_out = OT_SCRAPE_CHUNK_SIZE;
-    zres = deflate( strm, zaction );
-    if( ( zres < Z_OK ) && ( zres != Z_BUF_ERROR ) )
-      fprintf( stderr, "deflate() failed while in fullscrape_increase(%d).\n", zaction );
-    *r = (char*)strm->next_out;
-  }
-#endif
-
-  return 0;
+static char * fullscrape_write_one( ot_tasktype mode, char *r, ot_peerlist *peer_list, ot_hash *hash ) {
+  switch( mode & TASK_TASK_MASK ) {
+    case TASK_FULLSCRAPE:
+    default:
+      /* push hash as bencoded string */
+      *r++='2'; *r++='0'; *r++=':';
+      memcpy( r, hash, sizeof(ot_hash) ); r += sizeof(ot_hash);
+      /* push rest of the scrape string */
+      r += sprintf( r, "d8:completei%zde10:downloadedi%zde10:incompletei%zdee", peer_list->seed_count, peer_list->down_count, peer_list->peer_count-peer_list->seed_count );
+
+      break;
+    case TASK_FULLSCRAPE_TPB_ASCII:
+      to_hex( r, *hash ); r+= 2 * sizeof(ot_hash);
+      r += sprintf( r, ":%zd:%zd\n", peer_list->seed_count, peer_list->peer_count-peer_list->seed_count );
+      break;
+    case TASK_FULLSCRAPE_TPB_ASCII_PLUS:
+      to_hex( r, *hash ); r+= 2 * sizeof(ot_hash);
+      r += sprintf( r, ":%zd:%zd:%zd\n", peer_list->seed_count, peer_list->peer_count-peer_list->seed_count, peer_list->down_count );
+      break;
+    case TASK_FULLSCRAPE_TPB_BINARY:
+      memcpy( r, *hash, sizeof(ot_hash) ); r += sizeof(ot_hash);
+      *(uint32_t*)(r+0) = htonl( (uint32_t)  peer_list->seed_count );
+      *(uint32_t*)(r+4) = htonl( (uint32_t)( peer_list->peer_count-peer_list->seed_count) );
+      r+=8;
+      break;
+    case TASK_FULLSCRAPE_TPB_URLENCODED:
+      r += fmt_urlencoded( r, (char *)*hash, 20 );
+      r += sprintf( r, ":%zd:%zd\n", peer_list->seed_count, peer_list->peer_count-peer_list->seed_count );
+      break;
+    case TASK_FULLSCRAPE_TRACKERSTATE:
+      to_hex( r, *hash ); r+= 2 * sizeof(ot_hash);
+      r += sprintf( r, ":%zd:%zd\n", peer_list->base, peer_list->down_count );
+      break;
+    }
+    return r;
 }
 
 static void fullscrape_make( int *iovec_entries, struct iovec **iovector, ot_tasktype mode ) {
   int      bucket;
   char    *r, *re;
-#ifdef WANT_COMPRESSION_GZIP
-  char     compress_buffer[OT_SCRAPE_MAXENTRYLEN];
-  z_stream strm;
-#endif
 
   /* Setup return vector... */
   *iovec_entries = 0;
   *iovector = NULL;
-  if( !( r = iovec_increase( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE ) ) )
+  r = iovec_increase( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE );
+  if( !r )
     return;
 
   /* re points to low watermark */
   re = r + OT_SCRAPE_CHUNK_SIZE - OT_SCRAPE_MAXENTRYLEN;
 
-#ifdef WANT_COMPRESSION_GZIP
-  if( mode & TASK_FLAG_GZIP ) {
-    re += OT_SCRAPE_MAXENTRYLEN;
-    byte_zero( &strm, sizeof(strm) );
-    strm.next_in   = (uint8_t*)compress_buffer;
-    strm.next_out  = (uint8_t*)r;
-    strm.avail_out = OT_SCRAPE_CHUNK_SIZE;
-    if( deflateInit2(&strm,7,Z_DEFLATED,31,8,Z_DEFAULT_STRATEGY) != Z_OK )
-      fprintf( stderr, "not ok.\n" );
-    r = compress_buffer;
-  }
-#endif
-
   if( ( mode & TASK_TASK_MASK ) == TASK_FULLSCRAPE )
     r += sprintf( r, "d5:filesd" );
 
@@ -153,66 +140,98 @@ static void fullscrape_make( int *iovec_entries, struct iovec **iovector, ot_tas
   for( bucket=0; bucket<OT_BUCKET_COUNT; ++bucket ) {
     /* Get exclusive access to that bucket */
     ot_vector *torrents_list = mutex_bucket_lock( bucket );
-    size_t tor_offset;
+    ot_torrent *torrents = (ot_torrent*)(torrents_list->data);
+    size_t i;
 
     /* For each torrent in this bucket.. */
-    for( tor_offset=0; tor_offset<torrents_list->size; ++tor_offset ) {
-      /* Address torrents members */
-      ot_peerlist *peer_list = ( ((ot_torrent*)(torrents_list->data))[tor_offset] ).peer_list;
-      ot_hash     *hash      =&( ((ot_torrent*)(torrents_list->data))[tor_offset] ).hash;
-
-      switch( mode & TASK_TASK_MASK ) {
-      case TASK_FULLSCRAPE:
-      default:
-        /* push hash as bencoded string */
-        *r++='2'; *r++='0'; *r++=':';
-        memcpy( r, hash, sizeof(ot_hash) ); r += sizeof(ot_hash);
-        /* push rest of the scrape string */
-        r += sprintf( r, "d8:completei%zde10:downloadedi%zde10:incompletei%zdee", peer_list->seed_count, peer_list->down_count, peer_list->peer_count-peer_list->seed_count );
-
-        break;
-      case TASK_FULLSCRAPE_TPB_ASCII:
-        to_hex( r, *hash ); r+= 2 * sizeof(ot_hash);
-        r += sprintf( r, ":%zd:%zd\n", peer_list->seed_count, peer_list->peer_count-peer_list->seed_count );
-        break;
-      case TASK_FULLSCRAPE_TPB_ASCII_PLUS:
-        to_hex( r, *hash ); r+= 2 * sizeof(ot_hash);
-        r += sprintf( r, ":%zd:%zd:%zd\n", peer_list->seed_count, peer_list->peer_count-peer_list->seed_count, peer_list->down_count );
-        break;
-      case TASK_FULLSCRAPE_TPB_BINARY:
-        memcpy( r, *hash, sizeof(ot_hash) ); r += sizeof(ot_hash);
-        *(uint32_t*)(r+0) = htonl( (uint32_t)  peer_list->seed_count );
-        *(uint32_t*)(r+4) = htonl( (uint32_t)( peer_list->peer_count-peer_list->seed_count) );
-        r+=8;
-        break;
-      case TASK_FULLSCRAPE_TPB_URLENCODED:
-        r += fmt_urlencoded( r, (char *)*hash, 20 );
-        r += sprintf( r, ":%zd:%zd\n", peer_list->seed_count, peer_list->peer_count-peer_list->seed_count );
-        break;
-      case TASK_FULLSCRAPE_TRACKERSTATE:
-        to_hex( r, *hash ); r+= 2 * sizeof(ot_hash);
-        r += sprintf( r, ":%zd:%zd\n", peer_list->base, peer_list->down_count );
-        break;
+    for( i=0; i<torrents_list->size; ++i ) {
+      r = fullscrape_write_one( mode, r, torrents[i].peer_list, &torrents[i].hash );
+
+      if( r > re) {
+        /* Allocate a fresh output buffer at the end of our buffers list */
+        r = iovec_fix_increase_or_free( iovec_entries, iovector, r, OT_SCRAPE_CHUNK_SIZE );
+        if( !r )
+          return mutex_bucket_unlock( bucket, 0 );
+
+        /* re points to low watermark */
+        re = r + OT_SCRAPE_CHUNK_SIZE - OT_SCRAPE_MAXENTRYLEN;
       }
+    }
+
+    /* All torrents done: release lock on current bucket */
+    mutex_bucket_unlock( bucket, 0 );
+
+    /* Parent thread died? */
+    if( !g_opentracker_running )
+      return;
+  }
+
+  if( ( mode & TASK_TASK_MASK ) == TASK_FULLSCRAPE )
+    r += sprintf( r, "ee" );
+
+  /* Release unused memory in current output buffer */
+  iovec_fixlast( iovec_entries, iovector, r );
+}
 
 #ifdef WANT_COMPRESSION_GZIP
-     if( mode & TASK_FLAG_GZIP ) {
-        int zres;
-        strm.next_in  = (uint8_t*)compress_buffer;
-        strm.avail_in = r - compress_buffer;
+
+static void fullscrape_make_gzip( int *iovec_entries, struct iovec **iovector, ot_tasktype mode ) {
+  int      bucket;
+  char    *r;
+  int      zres;
+  z_stream strm;
+
+  /* Setup return vector... */
+  *iovec_entries = 0;
+  *iovector = NULL;
+  r = iovec_increase( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE );
+  if( !r )
+    return;
+
+  byte_zero( &strm, sizeof(strm) );
+  strm.next_out  = (uint8_t*)r;
+  strm.avail_out = OT_SCRAPE_CHUNK_SIZE;
+  if( deflateInit2(&strm,7,Z_DEFLATED,31,8,Z_DEFAULT_STRATEGY) != Z_OK )
+    fprintf( stderr, "not ok.\n" );
+
+  if( ( mode & TASK_TASK_MASK ) == TASK_FULLSCRAPE ) {
+    strm.next_in   = (uint8_t*)"d5:filesd";
+    strm.avail_in  = strlen("d5:filesd");
+    zres = deflate( &strm, Z_NO_FLUSH );
+  }
+
+  /* For each bucket... */
+  for( bucket=0; bucket<OT_BUCKET_COUNT; ++bucket ) {
+    /* Get exclusive access to that bucket */
+    ot_vector *torrents_list = mutex_bucket_lock( bucket );
+    ot_torrent *torrents = (ot_torrent*)(torrents_list->data);
+    size_t i;
+
+    /* For each torrent in this bucket.. */
+    for( i=0; i<torrents_list->size; ++i ) {
+      char compress_buffer[OT_SCRAPE_MAXENTRYLEN];
+      r = fullscrape_write_one( mode, compress_buffer, torrents[i].peer_list, &torrents[i].hash );
+      strm.next_in   = (uint8_t*)compress_buffer;
+      strm.avail_in  = r - compress_buffer;
+      zres = deflate( &strm, Z_NO_FLUSH );
+      if( ( zres < Z_OK ) && ( zres != Z_BUF_ERROR ) )
+        fprintf( stderr, "deflate() failed while in fullscrape_make().\n" );
+
+      /* Check if there still is enough buffer left */
+      while( !strm.avail_out ) {
+        /* Allocate a fresh output buffer at the end of our buffers list */
+        r = iovec_fix_increase_or_free( iovec_entries, iovector, strm.next_out, OT_SCRAPE_CHUNK_SIZE );
+        if( !r ) {
+          fprintf( stderr, "Problem with iovec_fix_increase_or_free\n" );
+          deflateEnd(&strm);
+          return mutex_bucket_unlock( bucket, 0 );
+        }
+        strm.next_out  = (uint8_t*)r;
+        strm.avail_out = OT_SCRAPE_CHUNK_SIZE;
         zres = deflate( &strm, Z_NO_FLUSH );
         if( ( zres < Z_OK ) && ( zres != Z_BUF_ERROR ) )
           fprintf( stderr, "deflate() failed while in fullscrape_make().\n" );
-        r = (char*)strm.next_out;
       }
-#endif
-
-      /* Check if there still is enough buffer left */
-      while( r >= re )
-       if( fullscrape_increase( iovec_entries, iovector, &r, &re WANT_COMPRESSION_GZIP_PARAM( &strm, mode, Z_NO_FLUSH ) ) )
-         return mutex_bucket_unlock( bucket, 0 );
-
-      IF_COMPRESSION( r = compress_buffer; )
     }
 
     /* All torrents done: release lock on current bucket */
@@ -223,27 +242,41 @@ static void fullscrape_make( int *iovec_entries, struct iovec **iovector, ot_tas
       return;
   }
 
-  if( ( mode & TASK_TASK_MASK ) == TASK_FULLSCRAPE )
-    r += sprintf( r, "ee" );
+  if( ( mode & TASK_TASK_MASK ) == TASK_FULLSCRAPE ) {
+    strm.next_in = (uint8_t*)"ee";
+    strm.avail_in = strlen("ee");
+  }
 
-#ifdef WANT_COMPRESSION_GZIP
-  if( mode & TASK_FLAG_GZIP ) {
-    strm.next_in  = (uint8_t*)compress_buffer;
-    strm.avail_in = r - compress_buffer;
+  if( deflate( &strm, Z_FINISH ) < Z_OK )
+    fprintf( stderr, "deflate() failed while in fullscrape_make()'s endgame.\n" );
+
+  if( !strm.avail_out ) {
+    unsigned int pending;
+    int bits;
+    deflatePending( &strm, &pending, &bits);
+    pending += ( bits ? 1 : 0 );
+
+    /* Allocate a fresh output buffer at the end of our buffers list */
+    r = iovec_fix_increase_or_free( iovec_entries, iovector, strm.next_out, pending );
+    if( !r ) {
+      fprintf( stderr, "Problem with iovec_fix_increase_or_free\n" );
+      deflateEnd(&strm);
+      return mutex_bucket_unlock( bucket, 0 );
+    }
+    strm.next_out  = (uint8_t*)r;
+    strm.avail_out = pending;
     if( deflate( &strm, Z_FINISH ) < Z_OK )
       fprintf( stderr, "deflate() failed while in fullscrape_make()'s endgame.\n" );
-    r = (char*)strm.next_out;
-
-    while( r >= re )
-      if( fullscrape_increase( iovec_entries, iovector, &r, &re WANT_COMPRESSION_GZIP_PARAM( &strm, mode, Z_FINISH ) ) )
-        return mutex_bucket_unlock( bucket, 0 );
-    deflateEnd(&strm);
   }
-#endif
 
   /* Release unused memory in current output buffer */
-  iovec_fixlast( iovec_entries, iovector, r );
+  iovec_fixlast( iovec_entries, iovector, strm.next_out );
+
+  deflateEnd(&strm);
 }
+/* WANT_COMPRESSION_GZIP */
 #endif
 
+/* WANT_FULLSCRAPE */
+#endif
 const char *g_version_fullscrape_c = "$Source$: $Revision$\n";