Stopped doing assignments inside expressions.
authorDenis Vlasenko <vda.linux@googlemail.com>
Fri, 5 Jan 2007 19:49:02 +0000 (19:49 -0000)
committerDenis Vlasenko <vda.linux@googlemail.com>
Fri, 5 Jan 2007 19:49:02 +0000 (19:49 -0000)
Who wrote this gem, I wonder?

n -= (e = (e = gunzip_wsize - ((d &= gunzip_wsize - 1) > w ? d : w)) > n ? n : e);

archival/libunarchive/decompress_uncompress.c
archival/libunarchive/decompress_unzip.c

index ff98254..8ce3cba 100644 (file)
 #undef MAXSEG_64K
 #define MAXCODE(n)     (1L << (n))
 
-/* Block compress mode -C compatible with 2.0 */
-static int block_mode = BLOCK_MODE;
-
-/* user settable max # bits/code */
-static int maxbits = BITS;
-
 #define        htabof(i)                               htab[i]
 #define        codetabof(i)                    codetab[i]
 #define        tab_prefixof(i)                 codetabof(i)
@@ -109,25 +103,38 @@ uncompress(int fd_in, int fd_out)
        RESERVE_CONFIG_UBUFFER(outbuf, OBUFSIZ + 2048);
        unsigned char htab[HSIZE];
        unsigned short codetab[HSIZE];
+
+       /* Hmm, these were statics - why?! */
+       /* user settable max # bits/code */
+       int maxbits; /* = BITS; */
+       /* block compress mode -C compatible with 2.0 */
+       int block_mode; /* = BLOCK_MODE; */
+
        memset(inbuf, 0, IBUFSIZ + 64);
        memset(outbuf, 0, OBUFSIZ + 2048);
 
        insize = 0;
 
-       inbuf[0] = xread_char(fd_in);
+       /* xread isn't good here, we have to return - caller may want
+        * to do some cleanup (e.g. delete incomplete unpacked file etc) */
+       if (full_read(fd_in, inbuf, 1) != 1) {
+               bb_error_msg("short read");
+               return -1;
+       }
 
        maxbits = inbuf[0] & BIT_MASK;
        block_mode = inbuf[0] & BLOCK_MODE;
        maxmaxcode = MAXCODE(maxbits);
 
        if (maxbits > BITS) {
-               bb_error_msg("compressed with %d bits, can only handle %d bits", maxbits,
-                                 BITS);
+               bb_error_msg("compressed with %d bits, can only handle "
+                               "%d bits", maxbits, BITS);
                return -1;
        }
 
-       maxcode = MAXCODE(n_bits = INIT_BITS) - 1;
-       bitmask = (1 << n_bits) - 1;
+       n_bits = INIT_BITS;
+       maxcode = MAXCODE(INIT_BITS) - 1;
+       bitmask = (1 << INIT_BITS) - 1;
        oldcode = -1;
        finchar = 0;
        outpos = 0;
@@ -143,13 +150,14 @@ uncompress(int fd_in, int fd_out)
        }
 
        do {
-         resetbuf:;
+ resetbuf:
                {
                        int i;
                        int e;
                        int o;
 
-                       e = insize - (o = (posbits >> 3));
+                       o = posbits >> 3;
+                       e = insize - o;
 
                        for (i = 0; i < e; ++i)
                                inbuf[i] = inbuf[i + o];
@@ -160,6 +168,7 @@ uncompress(int fd_in, int fd_out)
 
                if (insize < (int) (IBUFSIZ + 64) - IBUFSIZ) {
                        rsize = safe_read(fd_in, inbuf + insize, IBUFSIZ);
+//error check??
                        insize += rsize;
                }
 
@@ -184,8 +193,8 @@ uncompress(int fd_in, int fd_out)
                        {
                                unsigned char *p = &inbuf[posbits >> 3];
 
-                               code =  ((((long) (p[0])) | ((long) (p[1]) << 8) |
-                                         ((long) (p[2]) << 16)) >> (posbits & 0x7)) & bitmask;
+                               code = ((((long) (p[0])) | ((long) (p[1]) << 8) |
+                                        ((long) (p[2]) << 16)) >> (posbits & 0x7)) & bitmask;
                        }
                        posbits += n_bits;
 
@@ -204,8 +213,9 @@ uncompress(int fd_in, int fd_out)
                                        ((posbits - 1) +
                                         ((n_bits << 3) -
                                          (posbits - 1 + (n_bits << 3)) % (n_bits << 3)));
-                               maxcode = MAXCODE(n_bits = INIT_BITS) - 1;
-                               bitmask = (1 << n_bits) - 1;
+                               n_bits = INIT_BITS;
+                               maxcode = MAXCODE(INIT_BITS) - 1;
+                               bitmask = (1 << INIT_BITS) - 1;
                                goto resetbuf;
                        }
 
@@ -238,13 +248,15 @@ uncompress(int fd_in, int fd_out)
                                code = tab_prefixof(code);
                        }
 
-                       *--stackp = (unsigned char) (finchar = tab_suffixof(code));
+                       finchar = tab_suffixof(code);
+                       *--stackp = (unsigned char) finchar;
 
                        /* And put them out in forward order */
                        {
                                int i;
 
-                               if (outpos + (i = (de_stack - stackp)) >= OBUFSIZ) {
+                               i = de_stack - stackp;
+                               if (outpos + i >= OBUFSIZ) {
                                        do {
                                                if (i > OBUFSIZ - outpos) {
                                                        i = OBUFSIZ - outpos;
@@ -256,12 +268,14 @@ uncompress(int fd_in, int fd_out)
                                                }
 
                                                if (outpos >= OBUFSIZ) {
-                                                       write(fd_out, outbuf, outpos);
+                                                       full_write(fd_out, outbuf, outpos);
+//error check??
                                                        USE_DESKTOP(total_written += outpos;)
                                                        outpos = 0;
                                                }
                                                stackp += i;
-                                       } while ((i = (de_stack - stackp)) > 0);
+                                               i = de_stack - stackp;
+                                       } while (i > 0);
                                } else {
                                        memcpy(outbuf + outpos, stackp, i);
                                        outpos += i;
@@ -269,7 +283,8 @@ uncompress(int fd_in, int fd_out)
                        }
 
                        /* Generate the new entry. */
-                       if ((code = free_ent) < maxmaxcode) {
+                       code = free_ent;
+                       if (code < maxmaxcode) {
                                tab_prefixof(code) = (unsigned short) oldcode;
                                tab_suffixof(code) = (unsigned char) finchar;
                                free_ent = code + 1;
@@ -282,7 +297,8 @@ uncompress(int fd_in, int fd_out)
        } while (rsize > 0);
 
        if (outpos > 0) {
-               write(fd_out, outbuf, outpos);
+               full_write(fd_out, outbuf, outpos);
+//error check??
                USE_DESKTOP(total_written += outpos;)
        }
 
index b4d62f1..7001c70 100644 (file)
@@ -116,7 +116,9 @@ static unsigned fill_bitbuffer(unsigned bitbuffer, unsigned *current, const unsi
                        /* Leave the first 4 bytes empty so we can always unwind the bitbuffer
                         * to the front of the bytebuffer, leave 4 bytes free at end of tail
                         * so we can easily top up buffer in check_trailer_gzip() */
-                       if (1 > (bytebuffer_size = safe_read(gunzip_src_fd, &bytebuffer[4], bytebuffer_max - 8)))
+                       bytebuffer_size = safe_read(gunzip_src_fd, &bytebuffer[4], bytebuffer_max - 8);
+                       if (1 > bytebuffer_size)
+//shouldn't we propagate error?
                                bb_error_msg_and_die("unexpected end of file");
                        bytebuffer_size += 4;
                        bytebuffer_offset = 4;
@@ -193,7 +195,7 @@ int huft_build(unsigned *b, const unsigned n,
        eob_len = n > 256 ? b[256] : BMAX;
 
        /* Generate counts for each bit length */
-       memset((void *)c, 0, sizeof(c));
+       memset(c, 0, sizeof(c));
        p = b;
        i = n;
        do {
@@ -215,11 +217,13 @@ int huft_build(unsigned *b, const unsigned n,
 
        /* Adjust last length count to fill out codes, if needed */
        for (y = 1 << j; j < i; j++, y <<= 1) {
-               if ((y -= c[j]) < 0) {
+               y -= c[j];
+               if (y < 0) {
                        return 2; /* bad input: more codes than bits */
                }
        }
-       if ((y -= c[i]) < 0) {
+       y -= c[i];
+       if (y < 0) {
                return 2;
        }
        c[i] += y;
@@ -229,14 +233,16 @@ int huft_build(unsigned *b, const unsigned n,
        p = c + 1;
        xp = x + 2;
        while (--i) { /* note that i == g from above */
-               *xp++ = (j += *p++);
+               j += *p++;
+               *xp++ = j;
        }
 
        /* Make a table of values in order of bit lengths */
        p = b;
        i = 0;
        do {
-               if ((j = *p++) != 0) {
+               j = *p++;
+               if (j != 0) {
                        v[x[j]++] = i;
                }
        } while (++i < n);
@@ -260,13 +266,17 @@ int huft_build(unsigned *b, const unsigned n,
                                w = ws[++htl];
 
                                /* compute minimum size table less than or equal to *m bits */
-                               z = (z = g - w) > *m ? *m : z; /* upper limit on table size */
-                               if ((f = 1 << (j = k - w)) > a + 1) { /* try a k-w bit table */
+                               z = g - w;
+                               z = z > *m ? *m : z; /* upper limit on table size */
+                               j = k - w;
+                               f = 1 << j;
+                               if (f > a + 1) { /* try a k-w bit table */
                                        /* too few codes for k-w bit table */
                                        f -= a + 1; /* deduct codes from patterns left */
                                        xp = c + k;
                                        while (++j < z) { /* try smaller tables up to z bits */
-                                               if ((f <<= 1) <= *++xp) {
+                                               f <<= 1;
+                                               if (f <= *++xp) {
                                                        break; /* enough codes to use up j bits */
                                                }
                                                f -= *xp; /* else deduct codes from patterns */
@@ -338,6 +348,8 @@ int huft_build(unsigned *b, const unsigned n,
  * tl, td: literal/length and distance decoder tables
  * bl, bd: number of bits decoded by tl[] and td[]
  */
+/* called with setup==1 once from inflate_block */
+/* called once with setup==0 from inflate_get_next_window */
 static int inflate_codes(huft_t * my_tl, huft_t * my_td, const unsigned my_bl, const unsigned my_bd, int setup)
 {
        static unsigned e;      /* table entry flag/number of extra bits */
@@ -371,7 +383,9 @@ static int inflate_codes(huft_t * my_tl, huft_t * my_td, const unsigned my_bl, c
 
        while (1) {                     /* do until end of block */
                b = fill_bitbuffer(b, &k, bl);
-               if ((e = (t = tl + ((unsigned) b & ml))->e) > 16)
+               t = tl + ((unsigned) b & ml);
+               e = t->e;
+               if (e > 16)
                        do {
                                if (e == 99) {
                                        bb_error_msg_and_die("inflate_codes error 1");
@@ -380,8 +394,9 @@ static int inflate_codes(huft_t * my_tl, huft_t * my_td, const unsigned my_bl, c
                                k -= t->b;
                                e -= 16;
                                b = fill_bitbuffer(b, &k, e);
-                       } while ((e =
-                                         (t = t->v.t + ((unsigned) b & mask_bits[e]))->e) > 16);
+                               t = t->v.t + ((unsigned) b & mask_bits[e]);
+                               e = t->e;
+                       } while (e > 16);
                b >>= t->b;
                k -= t->b;
                if (e == 16) {  /* then it's a literal */
@@ -407,7 +422,9 @@ static int inflate_codes(huft_t * my_tl, huft_t * my_td, const unsigned my_bl, c
 
                        /* decode distance of block to copy */
                        b = fill_bitbuffer(b, &k, bd);
-                       if ((e = (t = td + ((unsigned) b & md))->e) > 16)
+                       t = td + ((unsigned) b & md);
+                       e = t->e;
+                       if (e > 16)
                                do {
                                        if (e == 99)
                                                bb_error_msg_and_die("inflate_codes error 2");
@@ -415,9 +432,9 @@ static int inflate_codes(huft_t * my_tl, huft_t * my_td, const unsigned my_bl, c
                                        k -= t->b;
                                        e -= 16;
                                        b = fill_bitbuffer(b, &k, e);
-                               } while ((e =
-                                                 (t =
-                                                  t->v.t + ((unsigned) b & mask_bits[e]))->e) > 16);
+                                       t = t->v.t + ((unsigned) b & mask_bits[e]);
+                                       e = t->e;
+                               } while (e > 16);
                        b >>= t->b;
                        k -= t->b;
                        b = fill_bitbuffer(b, &k, e);
@@ -426,26 +443,30 @@ static int inflate_codes(huft_t * my_tl, huft_t * my_td, const unsigned my_bl, c
                        k -= e;
 
                        /* do the copy */
-do_copy:               do {
-                               n -= (e =
-                                         (e =
-                                          gunzip_wsize - ((d &= gunzip_wsize - 1) > w ? d : w)) > n ? n : e);
-                          /* copy to new buffer to prevent possible overwrite */
+ do_copy:
+                       do {
+                               /* Was: n -= (e = (e = gunzip_wsize - ((d &= gunzip_wsize - 1) > w ? d : w)) > n ? n : e); */
+                               /* Who wrote THAT?? rewritten as: */
+                               d &= gunzip_wsize - 1;
+                               e = gunzip_wsize - (d > w ? d : w);
+                               if (e > n) e = n;
+                               n -= e;
+
+                               /* copy to new buffer to prevent possible overwrite */
                                if (w - d >= e) {       /* (this test assumes unsigned comparison) */
                                        memcpy(gunzip_window + w, gunzip_window + d, e);
                                        w += e;
                                        d += e;
                                } else {
-                                  /* do it slow to avoid memcpy() overlap */
-                                  /* !NOMEMCPY */
+                                       /* do it slow to avoid memcpy() overlap */
+                                       /* !NOMEMCPY */
                                        do {
                                                gunzip_window[w++] = gunzip_window[d++];
                                        } while (--e);
                                }
                                if (w == gunzip_wsize) {
                                        gunzip_outbuf_count = (w);
-                                       if (n) resumeCopy = 1;
-                                       else resumeCopy = 0;
+                                       resumeCopy = (n != 0);
                                        //flush_gunzip_window();
                                        w = 0;
                                        return 1;
@@ -469,9 +490,12 @@ do_copy:           do {
        return 0;
 }
 
+/* called once (setup==1) from inflate_block */
+/* and once (setup==0) from inflate_get_next_window */
 static int inflate_stored(int my_n, int my_b_stored, int my_k_stored, int setup)
 {
        static unsigned n, b_stored, k_stored, w;
+
        if (setup) {
                n = my_n;
                b_stored = my_b_stored;
@@ -509,7 +533,8 @@ static int inflate_stored(int my_n, int my_b_stored, int my_k_stored, int setup)
  *
  * GLOBAL VARIABLES: bb, kk,
  */
- // Return values: -1 = inflate_stored, -2 = inflate_codes
+/* Return values: -1 = inflate_stored, -2 = inflate_codes */
+/* One callsite in inflate_get_next_window */
 static int inflate_block(int *e)
 {
        unsigned t;                     /* block type */
@@ -597,7 +622,8 @@ static int inflate_block(int *e)
                        l[i] = 8;
                }
                bl = 7;
-               if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0) {
+               i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl);
+               if (i != 0) {
                        return i;
                }
 
@@ -606,7 +632,8 @@ static int inflate_block(int *e)
                        l[i] = 5;
                }
                bd = 5;
-               if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1) {
+               i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd);
+               if (i > 1) {
                        huft_free(tl);
                        return i;
                }
@@ -745,19 +772,21 @@ static int inflate_block(int *e)
                /* build the decoding tables for literal/length and distance codes */
                bl = lbits;
 
-               if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0) {
+               i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl);
+               if (i != 0) {
                        if (i == 1) {
                                bb_error_msg_and_die("incomplete literal tree");
-                               huft_free(tl);
+                               /* huft_free(tl); */
                        }
                        return i;       /* incomplete code set */
                }
 
                bd = dbits;
-               if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0) {
+               i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd);
+               if (i != 0) {
                        if (i == 1) {
                                bb_error_msg_and_die("incomplete distance tree");
-                               huft_free(td);
+                               /* huft_free(td); */
                        }
                        huft_free(tl);
                        return i;       /* incomplete code set */
@@ -776,6 +805,7 @@ static int inflate_block(int *e)
        }
 }
 
+/* Two callsites, both in inflate_get_next_window */
 static void calculate_gunzip_crc(void)
 {
        int n;
@@ -785,6 +815,7 @@ static void calculate_gunzip_crc(void)
        gunzip_bytes_out += gunzip_outbuf_count;
 }
 
+/* One callsite in inflate_unzip */
 static int inflate_get_next_window(void)
 {
        static int method = -1; // Method == -1 for stored, -2 for codes
@@ -823,7 +854,8 @@ static int inflate_get_next_window(void)
        /* Doesnt get here */
 }
 
-/* Initialise bytebuffer, be careful not to overfill the buffer */
+/* Initialize bytebuffer, be careful not to overfill the buffer */
+/* Called from archival/unzip.c */
 void inflate_init(unsigned bufsize)
 {
        /* Set the bytebuffer size, default is same as gunzip_wsize */
@@ -832,11 +864,13 @@ void inflate_init(unsigned bufsize)
        bytebuffer_size = 0;
 }
 
+/* Called from archival/unzip.c */
 void inflate_cleanup(void)
 {
        free(bytebuffer);
 }
 
+/* Called from inflate_gunzip() and archival/unzip.c */
 USE_DESKTOP(long long) int
 inflate_unzip(int in, int out)
 {
@@ -864,7 +898,7 @@ inflate_unzip(int in, int out)
        while (1) {
                int ret = inflate_get_next_window();
                nwrote = full_write(out, gunzip_window, gunzip_outbuf_count);
-               if (nwrote == -1) {
+               if (nwrote != gunzip_outbuf_count) {
                        bb_perror_msg("write");
                        return -1;
                }
@@ -901,6 +935,7 @@ inflate_gunzip(int in, int out)
        count = bytebuffer_size - bytebuffer_offset;
        if (count < 8) {
                xread(in, &bytebuffer[bytebuffer_size], 8 - count);
+//shouldn't we propagate error?
                bytebuffer_size += 8 - count;
        }
        for (count = 0; count != 4; count++) {
@@ -917,7 +952,8 @@ inflate_gunzip(int in, int out)
        /* Validate decompression - size */
        if (gunzip_bytes_out !=
                (bytebuffer[bytebuffer_offset] | (bytebuffer[bytebuffer_offset+1] << 8) |
-               (bytebuffer[bytebuffer_offset+2] << 16) | (bytebuffer[bytebuffer_offset+3] << 24))) {
+               (bytebuffer[bytebuffer_offset+2] << 16) | (bytebuffer[bytebuffer_offset+3] << 24))
+       ) {
                bb_error_msg("incorrect length");
                return -1;
        }