#define ID_MAX_LEN 64
+enum compression
+ {
+ COMP_NONE,
+ COMP_SIMPLE,
+ COMP_ZLIB
+ };
+
struct sfm_reader
{
const char *file_name;
enum integer_format integer_format;
enum float_format float_format;
- bool compressed;
+ enum compression compression;
double bias;
};
size_t size, size_t count);
static void read_unknown_extension (struct sfm_reader *,
size_t size, size_t count);
-static void read_compressed_data (struct sfm_reader *, int max_cases);
+static void read_simple_compressed_data (struct sfm_reader *, int max_cases);
+static void read_zlib_compressed_data (struct sfm_reader *);
static struct text_record *open_text_record (
struct sfm_reader *, size_t size);
r.n_var_widths = 0;
r.allocated_var_widths = 0;
r.var_widths = 0;
- r.compressed = false;
+ r.compression = COMP_NONE;
if (argc - optind > 1)
printf ("Reading \"%s\":\n", r.file_name);
(long long int) ftello (r.file),
(long long int) ftello (r.file) + 4);
- if (r.compressed && max_cases > 0)
- read_compressed_data (&r, max_cases);
+ if (r.compression == COMP_SIMPLE)
+ {
+ if (max_cases > 0)
+ read_simple_compressed_data (&r, max_cases);
+ }
+ else if (r.compression == COMP_ZLIB)
+ read_zlib_compressed_data (&r);
fclose (r.file);
}
char creation_date[10];
char creation_time[9];
char file_label[65];
+ bool zmagic;
read_string (r, rec_type, sizeof rec_type);
read_string (r, eye_catcher, sizeof eye_catcher);
- if (strcmp ("$FL2", rec_type) != 0)
+ if (!strcmp ("$FL2", rec_type))
+ zmagic = false;
+ else if (!strcmp ("$FL3", rec_type))
+ zmagic = true;
+ else
sys_error (r, "This is not an SPSS system file.");
/* Identify integer format. */
weight_index = read_int (r);
ncases = read_int (r);
- r->compressed = compressed != 0;
+ if (!zmagic)
+ {
+ if (compressed == 0)
+ r->compression = COMP_NONE;
+ else if (compressed == 1)
+ r->compression = COMP_SIMPLE;
+ else if (compressed != 0)
+ sys_error (r, "SAV file header has invalid compression value "
+ "%"PRId32".", compressed);
+ }
+ else
+ {
+ if (compressed == 2)
+ r->compression = COMP_ZLIB;
+ else
+ sys_error (r, "ZSAV file header has invalid compression value "
+ "%"PRId32".", compressed);
+ }
/* Identify floating-point format and obtain compression bias. */
read_bytes (r, raw_bias, sizeof raw_bias);
printf ("File header record:\n");
printf ("\t%17s: %s\n", "Product name", eye_catcher);
printf ("\t%17s: %"PRId32"\n", "Layout code", layout_code);
- printf ("\t%17s: %"PRId32"\n", "Compressed", compressed);
+ printf ("\t%17s: %"PRId32" (%s)\n", "Compressed",
+ compressed,
+ r->compression == COMP_NONE ? "no compression"
+ : r->compression == COMP_SIMPLE ? "simple compression"
+ : r->compression == COMP_ZLIB ? "ZLIB compression"
+ : "<error>");
printf ("\t%17s: %"PRId32"\n", "Weight index", weight_index);
printf ("\t%17s: %"PRId32"\n", "Number of cases", ncases);
printf ("\t%17s: %g\n", "Compression bias", r->bias);
}
static void
-read_compressed_data (struct sfm_reader *r, int max_cases)
+read_simple_compressed_data (struct sfm_reader *r, int max_cases)
{
enum { N_OPCODES = 8 };
uint8_t opcodes[N_OPCODES];
}
}
}
+
+static void
+read_zlib_compressed_data (struct sfm_reader *r)
+{
+ long long int ofs;
+ long long int this_ofs, next_ofs, next_len;
+ long long int bias, zero;
+ long long int expected_uncmp_ofs, expected_cmp_ofs;
+ unsigned int block_size, n_blocks;
+ unsigned int i;
+
+ read_int (r);
+ ofs = ftello (r->file);
+ printf ("\n%08llx: ZLIB compressed data header:\n", ofs);
+
+ this_ofs = read_int64 (r);
+ next_ofs = read_int64 (r);
+ next_len = read_int64 (r);
+
+ printf ("\tzheader_ofs: 0x%llx\n", this_ofs);
+ if (this_ofs != ofs)
+ printf ("\t\t(Expected 0x%llx.)\n", ofs);
+ printf ("\tztrailer_ofs: 0x%llx\n", next_ofs);
+ printf ("\tztrailer_len: %lld\n", next_len);
+ if (next_len < 24 || next_len % 24)
+ printf ("\t\t(Trailer length is not a positive multiple of 24.)\n");
+
+ printf ("\n%08llx: 0x%llx bytes of ZLIB compressed data\n",
+ ofs + 8 * 3, next_ofs - (ofs + 8 * 3));
+
+ skip_bytes (r, next_ofs - (ofs + 8 * 3));
+
+ printf ("\n%08llx: ZLIB trailer fixed header:\n", next_ofs);
+ bias = read_int64 (r);
+ zero = read_int64 (r);
+ block_size = read_int (r);
+ n_blocks = read_int (r);
+ printf ("\tbias: %lld\n", bias);
+ printf ("\tzero: 0x%llx\n", zero);
+ if (zero != 0)
+ printf ("\t\t(Expected 0.)\n");
+ printf ("\tblock_size: 0x%x\n", block_size);
+ if (block_size != 0x3ff000)
+ printf ("\t\t(Expected 0x3ff000.)\n");
+ printf ("\tn_blocks: %u\n", n_blocks);
+ if (n_blocks != next_len / 24 - 1)
+ printf ("\t\t(Expected %llu.)\n", next_len / 24 - 1);
+
+ expected_uncmp_ofs = ofs;
+ expected_cmp_ofs = ofs + 24;
+ for (i = 0; i < n_blocks; i++)
+ {
+ long long int blockinfo_ofs = ftello (r->file);
+ unsigned long long int uncompressed_ofs = read_int64 (r);
+ unsigned long long int compressed_ofs = read_int64 (r);
+ unsigned int uncompressed_size = read_int (r);
+ unsigned int compressed_size = read_int (r);
+
+ printf ("\n%08llx: ZLIB block descriptor %d\n", blockinfo_ofs, i + 1);
+
+ printf ("\tuncompressed_ofs: 0x%llx\n", uncompressed_ofs);
+ if (uncompressed_ofs != expected_uncmp_ofs)
+ printf ("\t\t(Expected 0x%llx.)\n", ofs);
+
+ printf ("\tcompressed_ofs: 0x%llx\n", compressed_ofs);
+ if (compressed_ofs != expected_cmp_ofs)
+ printf ("\t\t(Expected 0x%llx.)\n", ofs + 24);
+
+ printf ("\tuncompressed_size: 0x%x\n", uncompressed_size);
+ if (i < n_blocks - 1 && uncompressed_size != block_size)
+ printf ("\t\t(Expected 0x%x.)\n", block_size);
+
+ printf ("\tcompressed_size: 0x%x\n", compressed_size);
+ if (i == n_blocks - 1 && compressed_ofs + compressed_size != next_ofs)
+ printf ("\t\t(This was expected to be 0x%llx.)\n",
+ next_ofs - compressed_size);
+
+ expected_uncmp_ofs += uncompressed_size;
+ expected_cmp_ofs += compressed_size;
+ }
+}
\f
/* Helpers for reading records that consist of structured text
strings. */