diff options
Diffstat (limited to 'src/hunspell/hunzip.cxx')
| -rw-r--r-- | src/hunspell/hunzip.cxx | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/src/hunspell/hunzip.cxx b/src/hunspell/hunzip.cxx new file mode 100644 index 0000000..b50599f --- /dev/null +++ b/src/hunspell/hunzip.cxx @@ -0,0 +1,193 @@ +#include <stdlib.h> +#include <string.h> +#include <stdio.h> + +#include "hunzip.hxx" + +#define CODELEN 65536 +#define BASEBITREC 5000 + +#define UNCOMPRESSED '\002' +#define MAGIC "hz0" +#define MAGIC_ENCRYPT "hz1" +#define MAGICLEN (sizeof(MAGIC) - 1) + +int Hunzip::fail(const char * err, const char * par) { + fprintf(stderr, err, par); + return -1; +} + +Hunzip::Hunzip(const char * file, const char * key) { + bufsiz = 0; + lastbit = 0; + inc = 0; + outc = 0; + dec = NULL; + fin = NULL; + filename = (char *) malloc(strlen(file) + 1); + if (filename) strcpy(filename, file); + if (getcode(key) == -1) bufsiz = -1; + else bufsiz = getbuf(); +} + +int Hunzip::getcode(const char * key) { + unsigned char c[2]; + int i, j, n, p; + int allocatedbit = BASEBITREC; + const char * enc = key; + + if (!filename) return -1; + + fin = fopen(filename, "rb"); + if (!fin) return -1; + + // read magic number + if ((fread(in, 1, 3, fin) < MAGICLEN) + || !(strncmp(MAGIC, in, MAGICLEN) == 0 || + strncmp(MAGIC_ENCRYPT, in, MAGICLEN) == 0)) { + return fail(MSG_FORMAT, filename); + } + + // check encryption + if (strncmp(MAGIC_ENCRYPT, in, MAGICLEN) == 0) { + unsigned char cs; + if (!key) return fail(MSG_KEY, filename); + if (fread(&c, 1, 1, fin) < 1) return fail(MSG_FORMAT, filename); + for (cs = 0; *enc; enc++) cs ^= *enc; + if (cs != c[0]) return fail(MSG_KEY, filename); + enc = key; + } else key = NULL; + + // read record count + if (fread(&c, 1, 2, fin) < 2) return fail(MSG_FORMAT, filename); + + if (key) { + c[0] ^= *enc; + if (*(++enc) == '\0') enc = key; + c[1] ^= *enc; + } + + n = ((int) c[0] << 8) + c[1]; + dec = (struct bit *) malloc(BASEBITREC * sizeof(struct bit)); + if (!dec) return fail(MSG_MEMORY, filename); + dec[0].v[0] = 0; + dec[0].v[1] = 0; + + // read codes + for (i = 0; i < n; i++) { + unsigned char l; + if (fread(c, 1, 2, fin) < 2) return fail(MSG_FORMAT, filename); + if (key) { + if (*(++enc) == '\0') enc = key; + c[0] ^= *enc; + if (*(++enc) == '\0') enc = key; + c[1] ^= *enc; + } + if (fread(&l, 1, 1, fin) < 1) return fail(MSG_FORMAT, filename); + if (key) { + if (*(++enc) == '\0') enc = key; + l ^= *enc; + } + if (fread(in, 1, l/8+1, fin) < (size_t) l/8+1) return fail(MSG_FORMAT, filename); + if (key) for (j = 0; j <= l/8; j++) { + if (*(++enc) == '\0') enc = key; + in[j] ^= *enc; + } + p = 0; + for (j = 0; j < l; j++) { + int b = (in[j/8] & (1 << (7 - (j % 8)))) ? 1 : 0; + int oldp = p; + p = dec[p].v[b]; + if (p == 0) { + lastbit++; + if (lastbit == allocatedbit) { + allocatedbit += BASEBITREC; + dec = (struct bit *) realloc(dec, allocatedbit * sizeof(struct bit)); + } + dec[lastbit].v[0] = 0; + dec[lastbit].v[1] = 0; + dec[oldp].v[b] = lastbit; + p = lastbit; + } + } + dec[p].c[0] = c[0]; + dec[p].c[1] = c[1]; + } + return 0; +} + +Hunzip::~Hunzip() +{ + if (dec) free(dec); + if (fin) fclose(fin); + if (filename) free(filename); +} + +int Hunzip::getbuf() { + int p = 0; + int o = 0; + do { + if (inc == 0) inbits = fread(in, 1, BUFSIZE, fin) * 8; + for (; inc < inbits; inc++) { + int b = (in[inc / 8] & (1 << (7 - (inc % 8)))) ? 1 : 0; + int oldp = p; + p = dec[p].v[b]; + if (p == 0) { + if (oldp == lastbit) { + fclose(fin); + fin = NULL; + // add last odd byte + if (dec[lastbit].c[0]) out[o++] = dec[lastbit].c[1]; + return o; + } + out[o++] = dec[oldp].c[0]; + out[o++] = dec[oldp].c[1]; + if (o == BUFSIZE) return o; + p = dec[p].v[b]; + } + } + inc = 0; + } while (inbits == BUFSIZE * 8); + return fail(MSG_FORMAT, filename); +} + +const char * Hunzip::getline() { + char linebuf[BUFSIZE]; + int l = 0, eol = 0, left = 0, right = 0; + if (bufsiz == -1) return NULL; + while (l < bufsiz && !eol) { + linebuf[l++] = out[outc]; + switch (out[outc]) { + case '\t': break; + case 31: { // escape + if (++outc == bufsiz) { + bufsiz = getbuf(); + outc = 0; + } + linebuf[l - 1] = out[outc]; + break; + } + case ' ': break; + default: if (((unsigned char) out[outc]) < 47) { + if (out[outc] > 32) { + right = out[outc] - 31; + if (++outc == bufsiz) { + bufsiz = getbuf(); + outc = 0; + } + } + if (out[outc] == 30) left = 9; else left = out[outc]; + linebuf[l-1] = '\n'; + eol = 1; + } + } + if (++outc == bufsiz) { + outc = 0; + bufsiz = fin ? getbuf(): -1; + } + } + if (right) strcpy(linebuf + l - 1, line + strlen(line) - right - 1); + else linebuf[l] = '\0'; + strcpy(line + left, linebuf); + return line; +} |