tracking filelen and nuking dependency on ftell

diff --git a/bsdiff.c b/bsdiff.c
index 799e48a..729fb3e 100644 (file)
--- a/bsdiff.c
+++ b/bsdiff.c
@@ -305,7 +305,7 @@ static int finishcompress(bz_stream* bz2, FILE* pf)
 int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, struct bsdiff_header* header)
 {
        off_t *I,*V;
-       off_t scan,pos,len;
+       off_t scan,pos,len,filelen;
        off_t lastscan,lastpos,lastoffset;
        off_t oldscore,scsc;
        off_t s,Sf,lenf,Sb,lenb;
@@ -329,6 +329,7 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
                ((eb=malloc(newsize+1))==NULL)) err(1,NULL);
        dblen=0;
        eblen=0;
+       filelen=0;
 
        /* Header is
                0       8        "BSDIFF40"
@@ -419,11 +420,13 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
                        bz2err = writecompress(&bz2, pf, buf, 8);
                        if (bz2err == -1)
                                errx(1, "writecompress");
+                       filelen += bz2err;
 
                        offtout((pos-lenb)-(lastpos+lenf),buf);
                        bz2err = writecompress(&bz2, pf, buf, 8);
                        if (bz2err == -1)
                                errx(1, "writecompress");
+                       filelen += bz2err;
 
                        lastscan=scan-lenb;
                        lastpos=pos-lenb;
@@ -433,11 +436,10 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
        bz2err = finishcompress(&bz2, pf);
        if (bz2err == -1)
                errx(1, "finishcompress");
+       filelen += bz2err;
 
        /* Compute size of compressed ctrl data */
-       if ((len = ftello(pf)) == -1)
-               err(1, "ftello64");
-       header->ctrl_block_length = len-32;
+       header->ctrl_block_length = filelen;
 
        /* Write compressed diff data */
        if (BZ_OK != (bz2err = BZ2_bzCompressInit(&bz2, 9, 0, 0)))
@@ -445,14 +447,14 @@ int bsdiff(uint8_t* old, off_t oldsize, uint8_t* new, off_t newsize, FILE* pf, s
        bz2err = writecompress(&bz2, pf, db, dblen);
        if (bz2err == -1)
                errx(1, "writecompress");
+       filelen += bz2err;
        bz2err = finishcompress(&bz2, pf);
        if (bz2err == -1)
                errx(1, "finishcompress");
+       filelen += bz2err;
 
        /* Compute size of compressed diff data */
-       if ((newsize = ftello(pf)) == -1)
-               err(1, "ftello64");
-       header->diff_block_length = newsize - len;
+       header->diff_block_length = filelen - header->ctrl_block_length;
 
        /* Write compressed extra data */
        if (BZ_OK != (bz2err = BZ2_bzCompressInit(&bz2, 9, 0, 0)))