moving core patching functionality out of main and into bspatch

diff --git a/bspatch.c b/bspatch.c
index 3df1b6d..47f7073 100644 (file)
--- a/bspatch.c
+++ b/bspatch.c
@@ -55,6 +55,77 @@ static int64_t offtin(uint8_t *buf)
        return y;
 }
 
+int bspatch(const uint8_t* old, const int oldsize, uint8_t* new, const int newsize, FILE* cpf, FILE* dpf, FILE* epf)
+{
+       BZFILE * cpfbz2, * dpfbz2, * epfbz2;
+       int cbz2err, dbz2err, ebz2err;
+       ssize_t bzctrllen,bzdatalen;
+       uint8_t buf[8];
+       int64_t oldpos,newpos;
+       int64_t ctrl[3];
+       int64_t lenread;
+       int64_t i;
+
+       if ((cpfbz2 = BZ2_bzReadOpen(&cbz2err, cpf, 0, 0, NULL, 0)) == NULL)
+               errx(1, "BZ2_bzReadOpen, bz2err = %d", cbz2err);
+       if ((dpfbz2 = BZ2_bzReadOpen(&dbz2err, dpf, 0, 0, NULL, 0)) == NULL)
+               errx(1, "BZ2_bzReadOpen, bz2err = %d", dbz2err);
+       if ((epfbz2 = BZ2_bzReadOpen(&ebz2err, epf, 0, 0, NULL, 0)) == NULL)
+               errx(1, "BZ2_bzReadOpen, bz2err = %d", ebz2err);
+
+       oldpos=0;newpos=0;
+       while(newpos<newsize) {
+               /* Read control data */
+               for(i=0;i<=2;i++) {
+                       lenread = BZ2_bzRead(&cbz2err, cpfbz2, buf, 8);
+                       if ((lenread < 8) || ((cbz2err != BZ_OK) &&
+                           (cbz2err != BZ_STREAM_END)))
+                               errx(1, "Corrupt patch\n");
+                       ctrl[i]=offtin(buf);
+               };
+
+               /* Sanity-check */
+               if(newpos+ctrl[0]>newsize)
+                       errx(1,"Corrupt patch\n");
+
+               /* Read diff string */
+               lenread = BZ2_bzRead(&dbz2err, dpfbz2, new + newpos, ctrl[0]);
+               if ((lenread < ctrl[0]) ||
+                   ((dbz2err != BZ_OK) && (dbz2err != BZ_STREAM_END)))
+                       errx(1, "Corrupt patch\n");
+
+               /* Add old data to diff string */
+               for(i=0;i<ctrl[0];i++)
+                       if((oldpos+i>=0) && (oldpos+i<oldsize))
+                               new[newpos+i]+=old[oldpos+i];
+
+               /* Adjust pointers */
+               newpos+=ctrl[0];
+               oldpos+=ctrl[0];
+
+               /* Sanity-check */
+               if(newpos+ctrl[1]>newsize)
+                       errx(1,"Corrupt patch\n");
+
+               /* Read extra string */
+               lenread = BZ2_bzRead(&ebz2err, epfbz2, new + newpos, ctrl[1]);
+               if ((lenread < ctrl[1]) ||
+                   ((ebz2err != BZ_OK) && (ebz2err != BZ_STREAM_END)))
+                       errx(1, "Corrupt patch\n");
+
+               /* Adjust pointers */
+               newpos+=ctrl[1];
+               oldpos+=ctrl[2];
+       };
+
+       /* Clean up the bzip2 reads */
+       BZ2_bzReadClose(&cbz2err, cpfbz2);
+       BZ2_bzReadClose(&dbz2err, dpfbz2);
+       BZ2_bzReadClose(&ebz2err, epfbz2);
+
+       return 0;
+}
+
 int main(int argc,char * argv[])
 {
        FILE * f, * cpf, * dpf, * epf;
@@ -63,7 +134,7 @@ int main(int argc,char * argv[])
        int fd;
        ssize_t oldsize,newsize;
        ssize_t bzctrllen,bzdatalen;
-       uint8_t header[32],buf[8];
+       uint8_t header[32];
        uint8_t *old, *new;
        int64_t oldpos,newpos;
        int64_t ctrl[3];
@@ -116,22 +187,16 @@ int main(int argc,char * argv[])
        if (fseeko(cpf, 32, SEEK_SET))
                err(1, "fseeko(%s, %lld)", argv[3],
                    (long long)32);
-       if ((cpfbz2 = BZ2_bzReadOpen(&cbz2err, cpf, 0, 0, NULL, 0)) == NULL)
-               errx(1, "BZ2_bzReadOpen, bz2err = %d", cbz2err);
        if ((dpf = fopen(argv[3], "r")) == NULL)
                err(1, "fopen(%s)", argv[3]);
        if (fseeko(dpf, 32 + bzctrllen, SEEK_SET))
                err(1, "fseeko(%s, %lld)", argv[3],
                    (long long)(32 + bzctrllen));
-       if ((dpfbz2 = BZ2_bzReadOpen(&dbz2err, dpf, 0, 0, NULL, 0)) == NULL)
-               errx(1, "BZ2_bzReadOpen, bz2err = %d", dbz2err);
        if ((epf = fopen(argv[3], "r")) == NULL)
                err(1, "fopen(%s)", argv[3]);
        if (fseeko(epf, 32 + bzctrllen + bzdatalen, SEEK_SET))
                err(1, "fseeko(%s, %lld)", argv[3],
                    (long long)(32 + bzctrllen + bzdatalen));
-       if ((epfbz2 = BZ2_bzReadOpen(&ebz2err, epf, 0, 0, NULL, 0)) == NULL)
-               errx(1, "BZ2_bzReadOpen, bz2err = %d", ebz2err);
 
        if(((fd=open(argv[1],O_RDONLY,0))<0) ||
                ((oldsize=lseek(fd,0,SEEK_END))==-1) ||
@@ -141,57 +206,8 @@ int main(int argc,char * argv[])
                (close(fd)==-1)) err(1,"%s",argv[1]);
        if((new=malloc(newsize+1))==NULL) err(1,NULL);
 
-       oldpos=0;newpos=0;
-       while(newpos<newsize) {
-               /* Read control data */
-               for(i=0;i<=2;i++) {
-                       lenread = BZ2_bzRead(&cbz2err, cpfbz2, buf, 8);
-                       if ((lenread < 8) || ((cbz2err != BZ_OK) &&
-                           (cbz2err != BZ_STREAM_END)))
-                               errx(1, "Corrupt patch\n");
-                       ctrl[i]=offtin(buf);
-               };
-
-               /* Sanity-check */
-               if(newpos+ctrl[0]>newsize)
-                       errx(1,"Corrupt patch\n");
-
-               /* Read diff string */
-               lenread = BZ2_bzRead(&dbz2err, dpfbz2, new + newpos, ctrl[0]);
-               if ((lenread < ctrl[0]) ||
-                   ((dbz2err != BZ_OK) && (dbz2err != BZ_STREAM_END)))
-                       errx(1, "Corrupt patch\n");
-
-               /* Add old data to diff string */
-               for(i=0;i<ctrl[0];i++)
-                       if((oldpos+i>=0) && (oldpos+i<oldsize))
-                               new[newpos+i]+=old[oldpos+i];
-
-               /* Adjust pointers */
-               newpos+=ctrl[0];
-               oldpos+=ctrl[0];
-
-               /* Sanity-check */
-               if(newpos+ctrl[1]>newsize)
-                       errx(1,"Corrupt patch\n");
-
-               /* Read extra string */
-               lenread = BZ2_bzRead(&ebz2err, epfbz2, new + newpos, ctrl[1]);
-               if ((lenread < ctrl[1]) ||
-                   ((ebz2err != BZ_OK) && (ebz2err != BZ_STREAM_END)))
-                       errx(1, "Corrupt patch\n");
-
-               /* Adjust pointers */
-               newpos+=ctrl[1];
-               oldpos+=ctrl[2];
-       };
-
-       /* Clean up the bzip2 reads */
-       BZ2_bzReadClose(&cbz2err, cpfbz2);
-       BZ2_bzReadClose(&dbz2err, dpfbz2);
-       BZ2_bzReadClose(&ebz2err, epfbz2);
-       if (fclose(cpf) || fclose(dpf) || fclose(epf))
-               err(1, "fclose(%s)", argv[3]);
+       if (bspatch(old, oldsize, new, newsize, cpf, dpf, epf))
+               err(1, "bspatch");
 
        /* Write the new file */
        if(((fd=open(argv[2],O_CREAT|O_TRUNC|O_WRONLY,0666))<0) ||