From 5dbad6735298418205e83a420e56e1ab6856f30b Mon Sep 17 00:00:00 2001
From: leitner <leitner>
Date: Mon, 8 Apr 2024 12:35:11 +0000
Subject: [PATCH] autofree mode for io_batch

---
 Makefile               | 32 +++++++++++------
 io/iob_adds.c          |  6 ++--
 io/iob_adds_free.c     |  6 ++--
 io/iob_bytesleft.c     |  2 +-
 io/iob_init.c          | 13 +++++++
 io/iob_init_autofree.c |  7 ++++
 io/iob_new.3           |  2 +-
 io/iob_new.c           |  2 +-
 io/iob_new_autofree.c  |  8 +++++
 io/iob_send.c          | 78 +++++++++++++++++++++++++++++++++++++-----
 io/iob_write.c         |  9 ++++-
 io_internal.h          |  1 +
 iob.h                  | 51 ++++++++++++++++++++++++++-
 test/iob.c             | 14 ++++----
 14 files changed, 194 insertions(+), 37 deletions(-)
 create mode 100644 io/iob_init.c
 create mode 100644 io/iob_init_autofree.c
 create mode 100644 io/iob_new_autofree.c

diff --git a/Makefile b/Makefile
index afb2d83..11647c7 100644
--- a/Makefile
+++ b/Makefile
@@ -614,21 +614,30 @@ iob_addfile.o: io/iob_addfile.c iob_internal.h iob.h libowfat/io.h \
 iob_addfile_close.o: io/iob_addfile_close.c iob_internal.h iob.h \
  libowfat/io.h libowfat/uint64.h libowfat/taia.h libowfat/tai.h \
  libowfat/uint32.h libowfat/compiler.h libowfat/array.h array.h
-iob_adds.o: io/iob_adds.c str.h libowfat/compiler.h iob.h libowfat/io.h \
+iob_adds.o: io/iob_adds.c iob_internal.h iob.h libowfat/io.h \
  libowfat/uint64.h libowfat/taia.h libowfat/tai.h libowfat/uint32.h \
- libowfat/array.h
-iob_adds_free.o: io/iob_adds_free.c str.h libowfat/compiler.h iob.h \
- libowfat/io.h libowfat/uint64.h libowfat/taia.h libowfat/tai.h \
- libowfat/uint32.h libowfat/array.h
-iob_bytesleft.o: io/iob_bytesleft.c iob.h libowfat/io.h libowfat/uint64.h \
- libowfat/taia.h libowfat/tai.h libowfat/uint32.h libowfat/compiler.h \
- libowfat/array.h
+ libowfat/compiler.h libowfat/array.h array.h
+iob_adds_free.o: io/iob_adds_free.c iob_internal.h iob.h libowfat/io.h \
+ libowfat/uint64.h libowfat/taia.h libowfat/tai.h libowfat/uint32.h \
+ libowfat/compiler.h libowfat/array.h array.h
+iob_bytesleft.o: io/iob_bytesleft.c iob_internal.h iob.h libowfat/io.h \
+ libowfat/uint64.h libowfat/taia.h libowfat/tai.h libowfat/uint32.h \
+ libowfat/compiler.h libowfat/array.h array.h
 iob_free.o: io/iob_free.c iob_internal.h iob.h libowfat/io.h \
  libowfat/uint64.h libowfat/taia.h libowfat/tai.h libowfat/uint32.h \
  libowfat/compiler.h libowfat/array.h array.h
+iob_init.o: io/iob_init.c byte.h libowfat/compiler.h iob_internal.h iob.h \
+ libowfat/io.h libowfat/uint64.h libowfat/taia.h libowfat/tai.h \
+ libowfat/uint32.h libowfat/array.h array.h
+iob_init_autofree.o: io/iob_init_autofree.c iob_internal.h iob.h \
+ libowfat/io.h libowfat/uint64.h libowfat/taia.h libowfat/tai.h \
+ libowfat/uint32.h libowfat/compiler.h libowfat/array.h array.h
 iob_new.o: io/iob_new.c byte.h libowfat/compiler.h iob_internal.h iob.h \
  libowfat/io.h libowfat/uint64.h libowfat/taia.h libowfat/tai.h \
  libowfat/uint32.h libowfat/array.h array.h
+iob_new_autofree.o: io/iob_new_autofree.c iob_internal.h iob.h \
+ libowfat/io.h libowfat/uint64.h libowfat/taia.h libowfat/tai.h \
+ libowfat/uint32.h libowfat/compiler.h libowfat/array.h array.h
 iob_prefetch.o: io/iob_prefetch.c iob_internal.h iob.h libowfat/io.h \
  libowfat/uint64.h libowfat/taia.h libowfat/tai.h libowfat/uint32.h \
  libowfat/compiler.h libowfat/array.h array.h
@@ -883,7 +892,8 @@ socket_tcp4.o: socket/socket_tcp4.c socket.h libowfat/compiler.h \
 socket_tcp4b.o: socket/socket_tcp4b.c windoze.h socket.h \
  libowfat/compiler.h libowfat/uint16.h libowfat/uint32.h ndelay.h
 socket_tcp6.o: socket/socket_tcp6.c haveip6.h socket.h \
- libowfat/compiler.h libowfat/uint16.h libowfat/uint32.h ndelay.h
+ libowfat/compiler.h libowfat/uint16.h libowfat/uint32.h ndelay.h \
+ windoze.h
 socket_tcp6b.o: socket/socket_tcp6b.c windoze.h haveip6.h socket.h \
  libowfat/compiler.h libowfat/uint16.h libowfat/uint32.h ndelay.h
 socket_tryreservein.o: socket/socket_tryreservein.c windoze.h socket.h \
@@ -1080,7 +1090,7 @@ DNS_OBJS=dns_dfd.o dns_domain.o dns_dtda.o dns_ip.o dns_ip6.o dns_ipq.o dns_ipq6
 CASE_OBJS=case_diffb.o case_diffs.o case_lowerb.o case_lowers.o case_starts.o 
 MULT_OBJS=imult16.o imult32.o imult64.o range_arrayinbuf.o range_str2inbuf.o range_str4inbuf.o range_strinbuf.o umult16.o umult32.o umult64.o 
 ARRAY_OBJS=array_allocate.o array_bytes.o array_cat.o array_cat0.o array_catb.o array_cate.o array_cats.o array_cats0.o array_equal.o array_fail.o array_get.o array_length.o array_reset.o array_start.o array_trunc.o array_truncate.o iarray_allocate.o iarray_free.o iarray_get.o iarray_init.o iarray_length.o 
-IO_OBJS=io_appendfile.o io_block.o io_canread.o io_canwrite.o io_check.o io_close.o io_closeonexec.o io_createfile.o io_debugstring.o io_dontwantread.o io_dontwantwrite.o io_eagain.o io_eagain_read.o io_eagain_write.o io_fd.o io_finishandshutdown.o io_getcookie.o io_mmapwritefile.o io_nonblock.o io_passfd.o io_pipe.o io_readfile.o io_readwritefile.o io_receivefd.o io_sendfile.o io_setcookie.o io_sigpipe.o io_socketpair.o io_timedout.o io_timeout.o io_timeouted.o io_tryread.o io_tryreadtimeout.o io_trywrite.o io_trywritetimeout.o io_wait.o io_waitread.o io_waituntil.o io_waituntil2.o io_waitwrite.o io_wantread.o io_wantwrite.o iob_addbuf.o iob_addbuf_free.o iob_addbuf_internal.o iob_addbuf_munmap.o iob_addfile.o iob_addfile_close.o iob_adds.o iob_adds_free.o iob_bytesleft.o iob_free.o iob_new.o iob_prefetch.o iob_reset.o iob_send.o iob_write.o 
+IO_OBJS=io_appendfile.o io_block.o io_canread.o io_canwrite.o io_check.o io_close.o io_closeonexec.o io_createfile.o io_debugstring.o io_dontwantread.o io_dontwantwrite.o io_eagain.o io_eagain_read.o io_eagain_write.o io_fd.o io_finishandshutdown.o io_getcookie.o io_mmapwritefile.o io_nonblock.o io_passfd.o io_pipe.o io_readfile.o io_readwritefile.o io_receivefd.o io_sendfile.o io_setcookie.o io_sigpipe.o io_socketpair.o io_timedout.o io_timeout.o io_timeouted.o io_tryread.o io_tryreadtimeout.o io_trywrite.o io_trywritetimeout.o io_wait.o io_waitread.o io_waituntil.o io_waituntil2.o io_waitwrite.o io_wantread.o io_wantwrite.o iob_addbuf.o iob_addbuf_free.o iob_addbuf_internal.o iob_addbuf_munmap.o iob_addfile.o iob_addfile_close.o iob_adds.o iob_adds_free.o iob_bytesleft.o iob_free.o iob_new.o iob_prefetch.o iob_reset.o iob_send.o iob_write.o iom_abort.o iom_add.o iom_init.o iom_wait.o 
 TEXTCODE_OBJS=base64.o base64url.o fmt_base64.o fmt_base64url.o fmt_cescape.o fmt_foldwhitespace.o fmt_hexdump.o fmt_html.o fmt_html_tagarg.o fmt_jsonescape.o fmt_ldapescape.o fmt_ldapescape2.o fmt_quotedprintable.o fmt_to_array.o fmt_to_sa.o fmt_tofrom_array.o fmt_urlencoded.o fmt_uuencoded.o fmt_xml.o fmt_yenc.o scan_base64.o scan_base64url.o scan_cescape.o scan_hexdump.o scan_html.o scan_jsonescape.o scan_ldapescape.o scan_quotedprintable.o scan_to_array.o scan_to_sa.o scan_tofrom_array.o scan_urlencoded.o scan_uuencoded.o scan_yenc.o 
 CDB_OBJS=cdb.o cdb_hash.o cdb_make.o cdb_traverse.o 
 CRITBIT_OBJS=critbit.o 
@@ -1180,7 +1190,7 @@ uninstall:
 	rm -f $(LIBDIR)/libowfat.a
 
 VERSION=libowfat-0.34
-CURNAME=libowfat-0.32
+CURNAME=libowfat-0.34
 
 tar: clean rename compile_commands.json
 	rm -f dep libdep
diff --git a/io/iob_adds.c b/io/iob_adds.c
index 7441ab9..b6fc091 100644
--- a/io/iob_adds.c
+++ b/io/iob_adds.c
@@ -1,6 +1,6 @@
-#include "str.h"
-#include "iob.h"
+#include <string.h>
+#include "iob_internal.h"
 
 int iob_adds(io_batch* b,const char* s) {
-  return iob_addbuf(b,s,str_len(s));
+  return iob_addbuf(b,s,strlen(s));
 }
diff --git a/io/iob_adds_free.c b/io/iob_adds_free.c
index db8799f..0515efe 100644
--- a/io/iob_adds_free.c
+++ b/io/iob_adds_free.c
@@ -1,6 +1,6 @@
-#include "str.h"
-#include "iob.h"
+#include <string.h>
+#include "iob_internal.h"
 
 int iob_adds_free(io_batch* b,const char* s) {
-  return iob_addbuf_free(b,s,str_len(s));
+  return iob_addbuf_free(b,s,strlen(s));
 }
diff --git a/io/iob_bytesleft.c b/io/iob_bytesleft.c
index 40393cf..6f3e164 100644
--- a/io/iob_bytesleft.c
+++ b/io/iob_bytesleft.c
@@ -1,4 +1,4 @@
-#include "iob.h"
+#include "iob_internal.h"
 
 uint64 iob_bytesleft(const io_batch* b) {
   return b->bytesleft;
diff --git a/io/iob_init.c b/io/iob_init.c
new file mode 100644
index 0000000..56bb618
--- /dev/null
+++ b/io/iob_init.c
@@ -0,0 +1,13 @@
+#include <stdlib.h>
+#include "byte.h"
+#include "iob_internal.h"
+
+int iob_init(io_batch* b,size_t hint_entries) {
+  byte_zero(b,sizeof(io_batch));
+  if (hint_entries) {
+    if (!array_allocate(&b->b,sizeof(iob_entry),hint_entries))
+      return -1;
+    array_trunc(&b->b);
+  }
+  return 0;
+}
diff --git a/io/iob_init_autofree.c b/io/iob_init_autofree.c
new file mode 100644
index 0000000..7d0a1d6
--- /dev/null
+++ b/io/iob_init_autofree.c
@@ -0,0 +1,7 @@
+#include "iob_internal.h"
+
+int iob_init_autofree(io_batch* b,size_t hint_entries) {
+  int r=iob_init(b,hint_entries);
+  b->autofree=1;
+  return r;
+}
diff --git a/io/iob_new.3 b/io/iob_new.3
index 724f67e..4381d5f 100644
--- a/io/iob_new.3
+++ b/io/iob_new.3
@@ -4,7 +4,7 @@ iob_new \- create new I/O batch
 .SH SYNTAX
 .B #include <libowfat/iob.h>
 
-io_batch* \fBiob_new\fP(int hint_entries);
+io_batch* \fBiob_new\fP(size_t hint_entries);
 .SH DESCRIPTION
 iob_new creates a new I/O batch with enough space allocated for
 \fIhint_entries\fR entries (buffers or files).  This is purely a
diff --git a/io/iob_new.c b/io/iob_new.c
index dfd158f..f7c3e55 100644
--- a/io/iob_new.c
+++ b/io/iob_new.c
@@ -2,7 +2,7 @@
 #include "byte.h"
 #include "iob_internal.h"
 
-io_batch* iob_new(int hint_entries) {
+io_batch* iob_new(size_t hint_entries) {
   io_batch* b=(io_batch*)malloc(sizeof(io_batch));
   if (!b) return 0;
   byte_zero(b,sizeof(io_batch));
diff --git a/io/iob_new_autofree.c b/io/iob_new_autofree.c
new file mode 100644
index 0000000..d424ef6
--- /dev/null
+++ b/io/iob_new_autofree.c
@@ -0,0 +1,8 @@
+#include "iob_internal.h"
+
+io_batch* iob_new_autofree(size_t hint_entries) {
+  io_batch* b=iob_new(hint_entries);
+  if (b)
+    b->autofree=1;
+  return b;
+}
diff --git a/io/iob_send.c b/io/iob_send.c
index 9623b5b..5c6296d 100644
--- a/io/iob_send.c
+++ b/io/iob_send.c
@@ -7,6 +7,14 @@
 #include "iob_internal.h"
 #include <stdio.h>
 
+/*
+__        ___           _
+\ \      / (_)_ __   __| | _____      _____
+ \ \ /\ / /| | '_ \ / _` |/ _ \ \ /\ / / __|
+  \ V  V / | | | | | (_| | (_) \ V  V /\__ \
+   \_/\_/  |_|_| |_|\__,_|\___/ \_/\_/ |___/
+ */
+
 int64 iob_send(int64 s,io_batch* b) {
   /* Windows has a sendfile called TransmitFile, which can send one
    * header and one trailer buffer. */
@@ -108,6 +116,14 @@ int64 iob_send(int64 s,io_batch* b) {
 
 #else
 
+/*
+ _   _       _
+| | | |_ __ (_)_  __
+| | | | '_ \| \ \/ /
+| |_| | | | | |>  <
+ \___/|_| |_|_/_/\_\
+ */
+
 #include "havebsdsf.h"
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -145,7 +161,7 @@ int64 iob_send(int64 s,io_batch* b) {
 
   if (b->bytesleft==0) return 0;
   E=iarray_get(&io_fds,s);
-  if (!E) { errno=EBADF; return -3; }
+//  if (!E) { errno=EBADF; return -3; }
   last=(iob_entry*)(((char*)array_start(&b->b))+array_bytes(&b->b));
   v=alloca(b->bufs*sizeof(struct iovec));
   total=0;
@@ -167,6 +183,14 @@ int64 iob_send(int64 s,io_batch* b) {
     }
     headers=i;
 #ifdef HAVE_BSDSENDFILE
+
+/*
+ ____ ____  ____
+| __ ) ___||  _ \
+|  _ \___ \| | | |
+| |_) |__) | |_| |
+|____/____/|____/
+ */
     if (e+i<last && e[i].type==FROMFILE) {
 
 #ifdef DEBUGONLINUX
@@ -212,6 +236,14 @@ eagain:
       }
     }
 #else
+
+/*
+ _     _
+| |   (_)_ __  _   ___  __
+| |   | | '_ \| | | \ \/ /
+| |___| | | | | |_| |>  <
+|_____|_|_| |_|\__,_/_/\_\
+ */
     /* Linux has two ways to coalesce sent data; either setsockopt
      * TCP_CORK or sendto/sendmsg with MSG_MORE. MSG_MORE saves syscalls
      * in one scenario: when there is n buffers and then possibly one
@@ -245,7 +277,7 @@ eagain:
 	  if (!nozerocopy && sum>=8*1024) {
 	    /* MSG_ZEROCOPY has page table management overhead,
 	     * it only pays off after 8k or so */
-	    if (E->zerocopy==0) {
+	    if (E && E->zerocopy==0) {
 	      if (setsockopt(s, SOL_SOCKET, SO_ZEROCOPY, (int[]){ 1 },sizeof(int)) == 0) {
 		E->zerocopy=1;
 		ZEROCOPY=MSG_ZEROCOPY;
@@ -273,9 +305,18 @@ eagain:
 	      n = headers-skip; if (n > 50) n=50;
 	      for (i=0; i<n; ++i) l += v[skip+i].iov_len;
 //	      printf("writing %d records from offset %d, %d bytes\n", skip, n, l);
-	      msg.msg_iov=v + skip;
-	      msg.msg_iovlen=n;
-	      sent=sendmsg(s,&msg,MSG_MORE|ZEROCOPY);
+	      if (E && E->notsock)
+notsockwritev:
+		sent=writev(s,v+skip,n);
+	      else {
+		msg.msg_iov=v + skip;
+		msg.msg_iovlen=n;
+		sent=sendmsg(s,&msg,MSG_MORE|ZEROCOPY);
+		if (sent==-1 && errno==ENOTSOCK) {
+		  if (E) E->notsock=1;
+		  goto notsockwritev;
+		}
+	      }
 	      if (sent > 0) totalsent += sent;
 	      if (sent == l) continue;	// we sent as much as we wanted, go for next batch
 	      if (sent >= 0)	// we wrote something but not the whole batch
@@ -294,8 +335,20 @@ eagain:
 	    // if we get here, we wrote it all or we got an EAGAIN after
 	    // writing something. Treat as regular partial write.
 	    sent = totalsent;
-	  } else
-	    sent=sendmsg(s,&msg,MSG_MORE|ZEROCOPY);
+	  } else {
+	    if (E && E->notsock)
+notsockwritev2:
+	      sent=writev(s,v,headers);
+	    else {
+	      msg.msg_iov=v;
+	      msg.msg_iovlen=headers;
+	      sent=sendmsg(s,&msg,MSG_MORE|ZEROCOPY);
+	      if (sent==-1 && errno==ENOTSOCK) {
+		if (E) E->notsock=1;
+		goto notsockwritev2;
+	      }
+	    }
+	  }
 	}
       }
       if (sent==-1) {
@@ -345,6 +398,11 @@ eagain:
       for (i=0; e+i<last; ++i) {
 	if (e[i].n<=rest) {
 	  rest-=e[i].n;
+	  if (b->autofree) {
+	    if (e[i].cleanup)
+	      e[i].cleanup(e+i);
+	    e[i].cleanup=0;
+	  }
 	  ++b->next;
 	  if (!rest) break;
 	} else {
@@ -353,8 +411,10 @@ eagain:
 	  goto abort;
 	}
       }
-      io_eagain_write(s);
-      return total;
+      if (b->bytesleft==0) {
+	io_eagain_write(s);
+	return total;
+      }
     } else break;
   }
 abort:
diff --git a/io/iob_write.c b/io/iob_write.c
index dfd4974..c7a184b 100644
--- a/io/iob_write.c
+++ b/io/iob_write.c
@@ -11,7 +11,7 @@ int64 iob_write2(int64 s,io_batch* b,io_write_callback cb,io_sendfile_callback s
   total=0;
   if (!(e=array_get(&b->b,sizeof(iob_entry),b->next)))
     return -3;		/* can't happen error */
-  for (i=0; e+i<last; ++i) {
+  for (i=b->next; e+i<last; ++i) {
     int thatsit;
     if (!e[i].n) continue;
     if (e[i].type==FROMFILE)
@@ -27,6 +27,13 @@ int64 iob_write2(int64 s,io_batch* b,io_write_callback cb,io_sendfile_callback s
     total+=sent;
     b->bytesleft-=sent;
     if (thatsit) break;
+    // we have sent one full entry
+    if (b->autofree) {
+      if (e[i].cleanup)
+	e[i].cleanup(e+i);
+      e[i].cleanup=0;
+    }
+    ++b->next;
   }
   if (total == b->bytesleft)
     iob_reset(b);
diff --git a/io_internal.h b/io_internal.h
index c38e87b..aaa170a 100644
--- a/io_internal.h
+++ b/io_internal.h
@@ -50,6 +50,7 @@ typedef struct {
   unsigned int closed:1;	/* io_close called, but close deferred because of outstanding events */
   unsigned int zerocopy:1;	/* linux: setsockopt SO_ZEROCOPY done */
   unsigned int goterror:1;	/* got POLLERR|POLLHUP */
+  unsigned int notsock:1;	/* linux: got ENOTSOCKET from sendmsg, use writev */
 #ifdef __MINGW32__
   unsigned int readqueued:2;
   unsigned int writequeued:2;
diff --git a/iob.h b/iob.h
index c5b9231..63894da 100644
--- a/iob.h
+++ b/iob.h
@@ -21,34 +21,83 @@
 extern "C" {
 #endif
 
+/* you should not have to touch any of the internals */
 typedef struct io_batch {
+  /* array of iob_entry, defined in iob_internal.h */
   array b;
+  /* bytes left in the batch (starts as sum of lengths of all iob_entries */
   uint64 bytesleft;
+  /* next is the index of the first unsent batch in the array */
   long next,bufs,files;
+  /* Ask iob_send to free entries from the array as we go.
+   * Usually when iob_send returns 0 or error, you call iob_reset.
+   * You still have to call iob_reset even with this flag set, as
+   * autofree operates on the buffers in the array but does not free the
+   * array itself */
+  int autofree;
 } io_batch;
 
-io_batch* iob_new(int hint_entries);
+/* Initialize an io_batch. Return 0 on success, -1 on malloc failure for
+ * embedded array */
+int iob_init(io_batch* b,size_t hint_entries);
+/* initialize an io_batch that auto-frees entries as soon as
+ * iob_send/iob_write have written them. Return 0 on success, -1 on
+ * malloc failure for embedded array */
+int iob_init_autofree(io_batch* b,size_t hint_entries);
 
+/* malloc and initialize an io_batch */
+io_batch* iob_new(size_t hint_entries);
+/* malloc and initialize an io_batch that auto-frees entries as soon as
+ * iob_send/iob_write have written them */
+io_batch* iob_new_autofree(size_t hint_entries);
+
+/* queue buffer in io_batch */
 att_readn(2,3)
 int iob_addbuf(io_batch* b,const void* buf,uint64 n);
 
+/* queue buffer in io_batch, and give ownership to batch. */
+/* the io_batch functions will take care of freeing it. */
 att_readn(2,3)
 int iob_addbuf_free(io_batch* b,const void* buf,uint64 n);
 
+/* queue mmapped memory reagion in io_batch, and give ownership to batch. */
+/* the io_batch functions will take care of unmapping it. */
 att_readn(2,3)
 int iob_addbuf_munmap(io_batch* b,const void* buf,uint64 n);
 
+/* queue asciiz string in io_batch. */
 att_read(2)
 int iob_adds(io_batch* b,const char* s);
 
+/* queue asciiz string in io_batch, and give ownership to batch. */
+/* the io_batch functions will take care of freeing it. */
 att_read(2)
 int iob_adds_free(io_batch* b,const char* s);
+
+/* queue file contents in io_batch. */
 int iob_addfile(io_batch* b,int64 fd,uint64 off,uint64 n);
+
+/* queue file contents in io_batch, and give ownership to batch */
+/* the io_batch functions will take care of closing it. */
 int iob_addfile_close(io_batch* b,int64 fd,uint64 off,uint64 n);
+
+/* send (rest of) io_batch over socket s */
+/* return number of bytes written.
+ * return 0 means whole batch written successfully.
+ * return -1 means couldn't write more on non-blocking socket, try again later
+ * return -3 means error (errno set) */
 int64 iob_send(int64 s,io_batch* b);
+/* same as iob_send but don't use callback instead of write and
+ * sendfile. Use this to write via OpenSSL or so */
 int64 iob_write(int64 s,io_batch* b,io_write_callback cb);
+/* same as iob_write if the TLS library also has a sendfile function */
 int64 iob_write2(int64 s,io_batch* b,io_write_callback cb,io_sendfile_callback sfcb);
+
+/* iob_reset closes files and frees buffer in the io_batch, and the
+ * array with the buffer, but not the batch itself (in case it's a local
+ * variable and not malloced) */
 void iob_reset(io_batch* b);
+/* iob_free does iob_reset but also frees the batch itself */
 void iob_free(io_batch* b);
 void iob_prefetch(io_batch* b,uint64 bytes);
 uint64 iob_bytesleft(const io_batch* b);
diff --git a/test/iob.c b/test/iob.c
index 760401e..4fae590 100644
--- a/test/iob.c
+++ b/test/iob.c
@@ -1,7 +1,7 @@
 #include <assert.h>
-#include "iob.h"
-#include "buffer.h"
+#include "libowfat/iob.h"
 #include <unistd.h>
+#include <string.h>
 
 static int64 write_cb(int64 fd,const void* buf,uint64 len) {
   if (len>2) len=2;
@@ -11,14 +11,16 @@ static int64 write_cb(int64 fd,const void* buf,uint64 len) {
 int main() {
   int64 fd;
   io_batch* b;
-  int64 r;
+  char* fnord=strdup(" fnord\n");
+  assert(fnord);
   assert(io_readfile(&fd,"GNUmakefile"));
-  assert(b=iob_new(10));
+  assert((b=iob_new_autofree(10)));
   assert(iob_addbuf(b,"Huhu",4));
-  assert(iob_addbuf(b," fnord\n",7));
+  assert(iob_addbuf_free(b,fnord,7));
   assert(iob_addfile(b,fd,10,10));
   iob_send(1,b);
-#if 1
+#if 0
+  int64 r;
   do {
     r=iob_write(1,b,write_cb);
   } while (r>0);