1 files changed, 125 insertions, 0 deletions
diff --git a/deduper/libpuzzle/src/compress.c b/deduper/libpuzzle/src/compress.c
new file mode 100644
index 0000000..e71da95
--- /dev/null
+++ b/deduper/libpuzzle/src/compress.c
@@ -0,0 +1,125 @@
+#include "puzzle_common.h"
+#include "puzzle_p.h"
+#include "puzzle.h"
+#include "globals.h"
+
+void puzzle_init_compressed_cvec(PuzzleContext * const context,
+                                 PuzzleCompressedCvec * const compressed_cvec)
+{
+    (void) context;
+    compressed_cvec->sizeof_compressed_vec = (size_t) 0U;
+    compressed_cvec->vec = NULL;
+}
+
+void puzzle_free_compressed_cvec(PuzzleContext * const context,
+                                 PuzzleCompressedCvec * const compressed_cvec)
+{
+    (void) context;    
+    free(compressed_cvec->vec);
+    compressed_cvec->vec = NULL;    
+}
+
+int puzzle_compress_cvec(PuzzleContext * const context,
+                         PuzzleCompressedCvec * const compressed_cvec,
+                         const PuzzleCvec * const cvec)
+{
+#define PC_NM(X) ((unsigned char) ((X) + 2))
+    size_t remaining = cvec->sizeof_vec;
+    const signed char *ptr;    
+    unsigned char *cptr;
+
+    (void) context;
+    compressed_cvec->sizeof_compressed_vec =
+        (cvec->sizeof_vec + (size_t) 2U) / (size_t) 3U;
+    if ((compressed_cvec->vec =
+         calloc(compressed_cvec->sizeof_compressed_vec,
+                sizeof *compressed_cvec->vec)) == NULL) {
+        return -1;
+    }
+    ptr = cvec->vec;
+    cptr = compressed_cvec->vec;
+    while (remaining >= (size_t) 3U) {
+        *cptr++ = PC_NM(ptr[0]) + PC_NM(ptr[1]) * 5U +
+            PC_NM(ptr[2]) * (5U * 5U);
+        ptr += 3U;
+        remaining -= 3U;
+    }
+    if (remaining == (size_t) 1U) {
+        *cptr++ = PC_NM(ptr[0]);
+        compressed_cvec->vec[0] |= 128U;
+    } else if (remaining == (size_t) 2U) {
+        *cptr++ = PC_NM(ptr[0]) + PC_NM(ptr[1]) * 5U;
+        if (compressed_cvec->sizeof_compressed_vec < (size_t) 2U) {
+            puzzle_err_bug(__FILE__, __LINE__);
+        }
+        compressed_cvec->vec[1] |= 128U;
+    }
+    if ((size_t) (cptr - compressed_cvec->vec) !=
+        compressed_cvec->sizeof_compressed_vec) {
+        puzzle_err_bug(__FILE__, __LINE__);
+    }
+    return 0;
+}
+
+int puzzle_uncompress_cvec(PuzzleContext * const context,
+                           const PuzzleCompressedCvec * const compressed_cvec,
+                           PuzzleCvec * const cvec)
+{
+#define PC_FL(X) ((X) & 127U)
+#define PC_NP(X) ((signed char) (X) - 2)
+    
+    size_t remaining;    
+    unsigned char trailing_bits;
+    const unsigned char *cptr = compressed_cvec->vec;
+    signed char *ptr;
+    unsigned char c;
+
+    (void) context;
+    if (cvec->vec != NULL) {
+        puzzle_err_bug(__FILE__, __LINE__);
+    }
+    if ((remaining = compressed_cvec->sizeof_compressed_vec) < (size_t) 2U) {
+        puzzle_err_bug(__FILE__, __LINE__);
+    }
+    trailing_bits = ((cptr[0] & 128U) >> 7) | ((cptr[1] & 128U) >> 6);
+    if (trailing_bits > 2U) {
+        puzzle_err_bug(__FILE__, __LINE__);
+    }
+    cvec->sizeof_vec = (size_t) 3U *
+        (compressed_cvec->sizeof_compressed_vec - trailing_bits) +
+        trailing_bits;
+    if (compressed_cvec->sizeof_compressed_vec >
+        SIZE_MAX / (size_t) 3U - (size_t) 2U) {
+        puzzle_err_bug(__FILE__, __LINE__);
+    }
+    if ((cvec->vec = calloc(cvec->sizeof_vec, sizeof *cvec->vec)) == NULL) {
+        return -1;
+    }
+    if (trailing_bits != 0U) {
+        if (remaining <= (size_t) 0U) {
+            puzzle_err_bug(__FILE__, __LINE__);
+        }
+        remaining--;
+    }
+    ptr = cvec->vec;
+    while (remaining > (size_t) 0U) {
+        c = PC_FL(*cptr++);
+        *ptr++ = PC_NP(c % 5U);
+        c /= 5U;
+        *ptr++ = PC_NP(c % 5U);
+        c /= 5U;
+        *ptr++ = PC_NP(c % 5U);
+        remaining--;
+    }
+    if (trailing_bits == 1U) {
+        *ptr++ = PC_NP(PC_FL(*cptr) % 5U);        
+    } else if (trailing_bits == 2U) {
+        c = PC_FL(*cptr);
+        *ptr++ = PC_NP(c % 5U);
+        *ptr++ = PC_NP(c / 5U % 5U);        
+    }
+    if ((size_t) (ptr - cvec->vec) != cvec->sizeof_vec) {
+        puzzle_err_bug(__FILE__, __LINE__);
+    }
+    return 0;
+}