bzip2: more of code shrink

compressStream                                       503     473     -30
BZ2_bzCompress                                        78       -     -78
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 0/1 up/down: 0/-108)           Total: -108 bytes
   text    data     bss     dec     hex filename
 676300    2538   12104  690942   a8afe busybox_old
 676192    2538   12104  690834   a8a92 busybox_unstripped

2 files changed, 38 insertions, 64 deletions

diff --git a/archival/bz/bzlib.c b/archival/bz/bzlib.c
index cdb596cb1..9957c2fbd 100644
--- a/archival/bz/bzlib.c
+++ b/archival/bz/bzlib.c
@@ -76,11 +76,9 @@ void init_RL(EState* s)
 
 
 static
-Bool isempty_RL(EState* s)
+int isempty_RL(EState* s)
 {
-        if (s->state_in_ch < 256 && s->state_in_len > 0)
-                return False;
-        return True;
+        return (s->state_in_ch >= 256 || s->state_in_len <= 0);
 }
 
 
@@ -333,7 +331,7 @@ int BZ2_bzCompress(bz_stream *strm, int action)
                         }
 
 #ifdef FLUSH_IS_UNUSED
-case_BZ_M_FLUSHING:
+ case_BZ_M_FLUSHING:
                 case BZ_M_FLUSHING:
                         /*if (s->avail_in_expect != s->strm->avail_in)
                                 return BZ_SEQUENCE_ERROR;*/
diff --git a/archival/bzip2.c b/archival/bzip2.c
index 67df14416..76963365f 100644
--- a/archival/bzip2.c
+++ b/archival/bzip2.c
@@ -51,79 +51,55 @@ enum {
         IOBUF_SIZE = 8 * 1024
 };
 
+static uint8_t level;
+
+/* NB: compressStream() has to return -1 on errors, not die.
+ * bbunpack() will correctly clean up in this case
+ * (delete incomplete .bz2 file)
+ */
+
 /* Returns:
- * <0 on write errors (examine errno),
- * >0 on short writes (errno == 0)
- * 0  no error (entire input consumed, gimme more)
- * on "impossible" errors (internal bzip2 compressor bug) dies
+ * -1 on errors
+ * total written bytes so far otherwise
  */
 static
-ssize_t bz_write(bz_stream *strm, void* rbuf, ssize_t rlen, void *wbuf)
+USE_DESKTOP(long long) int bz_write(bz_stream *strm, void* rbuf, ssize_t rlen, void *wbuf)
 {
         int n, n2, ret;
 
         strm->avail_in = rlen;
-        strm->next_in  = rbuf;
+        strm->next_in = rbuf;
         while (1) {
                 strm->avail_out = IOBUF_SIZE;
                 strm->next_out = wbuf;
 
-                ret = BZ2_bzCompress(strm, BZ_RUN);
-                if (ret != BZ_RUN_OK)
+                ret = BZ2_bzCompress(strm, rlen ? BZ_RUN : BZ_FINISH);
+                if (ret != BZ_RUN_OK /* BZ_RUNning */
+                 && ret != BZ_FINISH_OK /* BZ_FINISHing, but not done yet */
+                 && ret != BZ_STREAM_END /* BZ_FINISHed */
+                ) {
                         bb_error_msg_and_die("internal error %d", ret);
-
-                n = IOBUF_SIZE - strm->avail_out;
-                if (n) {
-                        /* short reads must have errno == 0 */
-                        errno = 0;
-                        n2 = full_write(STDOUT_FILENO, wbuf, n);
-                        if (n2 != n)
-                                return n2 ? n2 : 1;
                 }
 
-                if (strm->avail_in == 0)
-                        return 0;
-        }
-}
-
-
-/*---------------------------------------------------*/
-static
-USE_DESKTOP(long long) int bz_write_tail(bz_stream *strm, void *wbuf)
-{
-        int n, n2, ret;
-        USE_DESKTOP(long long) int total;
-
-        total = -1;
-        while (1) {
-                strm->avail_out = IOBUF_SIZE;
-                strm->next_out = wbuf;
-
-                ret = BZ2_bzCompress(strm, BZ_FINISH);
-                if (ret != BZ_FINISH_OK && ret != BZ_STREAM_END)
-                        bb_error_msg_and_die("internal error %d", ret);
-
                 n = IOBUF_SIZE - strm->avail_out;
                 if (n) {
                         n2 = full_write(STDOUT_FILENO, wbuf, n);
-                        if (n2 != n)
-                                goto err;
+                        if (n2 != n) {
+                                if (n2 >= 0)
+                                        errno = 0; /* prevent bogus error message */
+                                bb_perror_msg(n2 >= 0 ? "short write" : "write error");
+                                return -1;
+                        }
                 }
 
                 if (ret == BZ_STREAM_END)
                         break;
+                if (rlen && strm->avail_in == 0)
+                        break;
         }
-
-        total = 0 USE_DESKTOP( + strm->total_out );
- err:
-#if ENABLE_FEATURE_CLEAN_UP
-        BZ2_bzCompressEnd(strm);
-#endif
-        return total;
+        return 0 USE_DESKTOP( + strm->total_out );
 }
 
-static uint8_t level;
-
 static
 USE_DESKTOP(long long) int compressStream(void)
 {
@@ -136,26 +112,26 @@ USE_DESKTOP(long long) int compressStream(void)
 #define wbuf (iobuf + IOBUF_SIZE)
 
         iobuf = xmalloc(2 * IOBUF_SIZE);
-
         BZ2_bzCompressInit(strm, level);
 
         while (1) {
                 count = full_read(STDIN_FILENO, rbuf, IOBUF_SIZE);
-                if (count < 0)
+                if (count < 0) {
                         bb_perror_msg("read error");
-                if (count <= 0)
-                        break;
-                count = bz_write(strm, rbuf, count, wbuf);
-                if (count) {
-                        bb_perror_msg(count < 0 ? "write error" : "short write");
+                        total = -1;
                         break;
                 }
+                /* if count == 0, bz_write finalizes compression */
+                total = bz_write(strm, rbuf, count, wbuf);
+                if (count == 0 || total < 0)
+                        break;
         }
 
-        total = bz_write_tail(strm, wbuf);
+#if ENABLE_FEATURE_CLEAN_UP
+        BZ2_bzCompressEnd(strm);
         free(iobuf);
-        /* we had no error _only_ if count == 0 */
-        return count == 0 ? total : -1;
+#endif
+        return total;
 }
 
 static