removing dependency on FILE* based BZ2 functions

diff --git a/bsdiff.c b/bsdiff.c
index c61a36c..7a7e0ef 100644 (file)
--- a/bsdiff.c
+++ b/bsdiff.c
@@ -238,6 +238,62 @@ static void offtout(off_t x,uint8_t *buf)
        if(x<0) buf[7]|=0x80;
 }
 
+static int writecompress(bz_stream* bz2, FILE* pf, const uint8_t* out, int size)
+{
+       int err;
+       char buffer[4096];
+
+       bz2->next_in = (char*)out;
+       bz2->avail_in = size;
+
+       for (;;)
+       {
+               bz2->next_out = buffer;
+               bz2->avail_out = sizeof(buffer);
+               if (BZ_RUN_OK != (err = BZ2_bzCompress(bz2, BZ_RUN)))
+                       return err;
+
+               if (bz2->avail_out < sizeof(buffer))
+               {
+                       const int written = sizeof(buffer) - bz2->avail_out;
+                       if (1 != fwrite(buffer, written, 1, pf))
+                               return BZ_IO_ERROR;
+               }
+
+               if (bz2->avail_in == 0)
+                       return BZ_OK;
+       }
+}
+
+static int finishcompress(bz_stream* bz2, FILE* pf)
+{
+       int err;
+       char buffer[4096];
+
+       for (;;)
+       {
+               bz2->next_out = buffer;
+               bz2->avail_out = sizeof(buffer);
+
+               err = BZ2_bzCompress(bz2, BZ_FINISH);
+               if (BZ_FINISH_OK != err && BZ_STREAM_END != err)
+                       return err;
+
+               if (bz2->avail_out < sizeof(buffer))
+               {
+                       const int written = sizeof(buffer) - bz2->avail_out;
+                       if (1 != fwrite(buffer, written, 1, pf))
+                               return BZ_IO_ERROR;
+               }
+
+               if (BZ_STREAM_END == err)
+                       break;
+       }
+
+       BZ2_bzCompressEnd(bz2);
+       return BZ_OK;
+}
+
 int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, struct bsdiff_header* header)
 {
        off_t *I,*V;
@@ -250,7 +306,8 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
        off_t dblen,eblen;
        uint8_t *db,*eb;
        uint8_t buf[8];
-       BZFILE * pfbz2;
+
+       bz_stream bz2 = {0};
        int bz2err;
 
 
@@ -281,8 +338,8 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
        header->new_file_length = newsize;
 
        /* Compute the differences, writing ctrl as we go */
-       if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
-               errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
+       if (BZ_OK != (bz2err = BZ2_bzCompressInit(&bz2, 9, 0, 0)))
+               errx(1, "BZ2_bzCompressInit, err = %d", bz2err);
        scan=0;len=0;
        lastscan=0;lastpos=0;lastoffset=0;
        while(scan<newsize) {
@@ -346,28 +403,28 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
                        eblen+=(scan-lenb)-(lastscan+lenf);
 
                        offtout(lenf,buf);
-                       BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
+                       bz2err = writecompress(&bz2, pf, buf, 8);
                        if (bz2err != BZ_OK)
-                               errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+                               errx(1, "writecompress, err = %d", bz2err);
 
                        offtout((scan-lenb)-(lastscan+lenf),buf);
-                       BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
+                       bz2err = writecompress(&bz2, pf, buf, 8);
                        if (bz2err != BZ_OK)
-                               errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+                               errx(1, "writecompress, err = %d", bz2err);
 
                        offtout((pos-lenb)-(lastpos+lenf),buf);
-                       BZ2_bzWrite(&bz2err, pfbz2, buf, 8);
+                       bz2err = writecompress(&bz2, pf, buf, 8);
                        if (bz2err != BZ_OK)
-                               errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
+                               errx(1, "writecompress, err = %d", bz2err);
 
                        lastscan=scan-lenb;
                        lastpos=pos-lenb;
                        lastoffset=pos-scan;
                };
        };
-       BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
+       bz2err = finishcompress(&bz2, pf);
        if (bz2err != BZ_OK)
-               errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
+               errx(1, "finishcompress, err = %d", bz2err);
 
        /* Compute size of compressed ctrl data */
        if ((len = ftello(pf)) == -1)
@@ -375,14 +432,14 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
        header->ctrl_block_length = len-32;
 
        /* Write compressed diff data */
-       if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
-               errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
-       BZ2_bzWrite(&bz2err, pfbz2, db, dblen);
+       if (BZ_OK != (bz2err = BZ2_bzCompressInit(&bz2, 9, 0, 0)))
+               errx(1, "BZ2_bzCompressInit, err = %d", bz2err);
+       bz2err = writecompress(&bz2, pf, db, dblen);
        if (bz2err != BZ_OK)
-               errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
-       BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
+               errx(1, "writecompress, err = %d", bz2err);
+       bz2err = finishcompress(&bz2, pf);
        if (bz2err != BZ_OK)
-               errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
+               errx(1, "finishcompress, err = %d", bz2err);
 
        /* Compute size of compressed diff data */
        if ((newsize = ftello(pf)) == -1)
@@ -390,14 +447,14 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
        header->diff_block_length = newsize - len;
 
        /* Write compressed extra data */
-       if ((pfbz2 = BZ2_bzWriteOpen(&bz2err, pf, 9, 0, 0)) == NULL)
-               errx(1, "BZ2_bzWriteOpen, bz2err = %d", bz2err);
-       BZ2_bzWrite(&bz2err, pfbz2, eb, eblen);
+       if (BZ_OK != (bz2err = BZ2_bzCompressInit(&bz2, 9, 0, 0)))
+               errx(1, "BZ2_bzCompressInit, err = %d", bz2err);
+       bz2err = writecompress(&bz2, pf, eb, eblen);
        if (bz2err != BZ_OK)
-               errx(1, "BZ2_bzWrite, bz2err = %d", bz2err);
-       BZ2_bzWriteClose(&bz2err, pfbz2, 0, NULL, NULL);
+               errx(1, "writecompress, err = %d", bz2err);
+       bz2err = finishcompress(&bz2, pf);
        if (bz2err != BZ_OK)
-               errx(1, "BZ2_bzWriteClose, bz2err = %d", bz2err);
+               errx(1, "finishcompress, err = %d", bz2err);
 
        /* Free the memory we used */
        free(db);