/src/zlib-ng/gzlib.c

Source
/* gzlib.c -- zlib functions common to reading and writing gzip files
 * Copyright (C) 2004-2024 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

#include "zbuild.h"
#include "zutil.h"
#include "zutil_p.h"
#include "gzguts.h"

#if defined(_WIN32)
#  define LSEEK _lseeki64
#else
#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
#  define LSEEK lseek64
#else
#  define LSEEK lseek
#endif
#endif

/* Local functions */
static gzFile gz_state_init(void);
static void gz_reset(gz_state *);
static gzFile gz_open(const void *, int, const char *);

/* Initialize struct for gzFile state */
static gzFile gz_state_init(void) {
    /* allocate gzFile structure to return */
    gz_state *state = (gz_state *)zng_alloc(sizeof(gz_state));
    if (state == NULL)
        return NULL;

    state->strm.zalloc = NULL;
    state->strm.zfree = NULL;
    state->strm.opaque = NULL;
    state->strm.next_in = NULL;

    state->size = 0;
    state->want = GZBUFSIZE;
    state->in = NULL;
    state->out = NULL;
    state->direct = 0;
    state->mode = GZ_NONE;
    state->level = Z_DEFAULT_COMPRESSION;
    state->strategy = Z_DEFAULT_STRATEGY;
    state->msg = NULL;
    return (gzFile)state;
}

void Z_INTERNAL gz_state_free(gz_state *state) {
    zng_free(state);
}

/* Reset gzip file state */
static void gz_reset(gz_state *state) {
    state->x.have = 0;              /* no output data available */
    if (state->mode == GZ_READ) {   /* for reading ... */
        state->eof = 0;             /* not at end of file */
        state->past = 0;            /* have not read past end yet */
        state->how = LOOK;          /* look for gzip header */
    }
    else                            /* for writing ... */
        state->reset = 0;           /* no deflateReset pending */
    state->seek = 0;                /* no seek request pending */
    gz_error(state, Z_OK, NULL);    /* clear error */
    state->x.pos = 0;               /* no uncompressed data yet */
    state->strm.avail_in = 0;       /* no input data yet */
}

/* Allocate in/out buffers for gzFile */
int Z_INTERNAL gz_buffer_alloc(gz_state *state) {
    int want = state->want;
    int in_size = want, out_size = want;

    if (state->mode == GZ_WRITE) {
        in_size = want * 2; // double input buffer for compression (ref: gzprintf)
        if (state->direct)
            out_size = 0; // output buffer not needed in write + direct mode
    } else if (state->mode == GZ_READ) {
        out_size = want * 2;  // double output buffer for decompression
    }

    state->buffers = (unsigned char *)zng_alloc_aligned((in_size + out_size), 64);
    state->in = state->buffers;
    if (out_size) {
        state->out = state->buffers + (in_size); // Outbuffer goes after inbuffer
    }

    /* Return error if memory allocation failed */
    if (state->in == NULL || (out_size && state->out == NULL)) {
        gz_buffer_free(state);
        gz_error(state, Z_MEM_ERROR, "out of memory");
        return -1;
    }

    state->size = want; // mark state as initialized
    return 0;
}

void Z_INTERNAL gz_buffer_free(gz_state *state) {
    zng_free_aligned(state->buffers);
    state->buffers = NULL;
    state->out = NULL;
    state->in = NULL;
    state->size = 0;
}

/* Open a gzip file either by name or file descriptor. */
static gzFile gz_open(const void *path, int fd, const char *mode) {
    gz_state *state;
    size_t len;
    int oflag;
#ifdef O_CLOEXEC
    int cloexec = 0;
#endif
#ifdef O_EXCL
    int exclusive = 0;
#endif

    /* check input */
    if (path == NULL)
        return NULL;

    /* Initialize gzFile state */
    state = (gz_state *)gz_state_init();
    if (state == NULL)
        return NULL;

    /* interpret mode */
    while (*mode) {
        if (*mode >= '0' && *mode <= '9') {
            state->level = *mode - '0';
        } else {
            switch (*mode) {
            case 'r':
                state->mode = GZ_READ;
                break;
#ifndef NO_GZCOMPRESS
            case 'w':
                state->mode = GZ_WRITE;
                break;
            case 'a':
                state->mode = GZ_APPEND;
                break;
#endif
            case '+':       /* can't read and write at the same time */
                gz_state_free(state);
                return NULL;
            case 'b':       /* ignore -- will request binary anyway */
                break;
#ifdef O_CLOEXEC
            case 'e':
                cloexec = 1;
                break;
#endif
#ifdef O_EXCL
            case 'x':
                exclusive = 1;
                break;
#endif
            case 'f':
                state->strategy = Z_FILTERED;
                break;
            case 'h':
                state->strategy = Z_HUFFMAN_ONLY;
                break;
            case 'R':
                state->strategy = Z_RLE;
                break;
            case 'F':
                state->strategy = Z_FIXED;
                break;
            case 'T':
                state->direct = 1;
                break;
            default:        /* could consider as an error, but just ignore */
                {}
            }
        }
        mode++;
    }

    /* must provide an "r", "w", or "a" */
    if (state->mode == GZ_NONE) {
        gz_state_free(state);
        return NULL;
    }

    /* can't force transparent read */
    if (state->mode == GZ_READ) {
        if (state->direct) {
            gz_state_free(state);
            return NULL;
        }
        state->direct = 1;      /* for empty file */
    }

    /* save the path name for error messages */
#ifdef WIDECHAR
    if (fd == -2) {
        len = wcstombs(NULL, (const wchar_t *)path, 0);
        if (len == (size_t)-1)
            len = 0;
    } else
#endif
        len = strlen((const char *)path);
    state->path = (char *)malloc(len + 1);
    if (state->path == NULL) {
        gz_state_free(state);
        return NULL;
    }
#ifdef WIDECHAR
    if (fd == -2)
        if (len) {
            wcstombs(state->path, (const wchar_t *)path, len + 1);
        } else {
            *(state->path) = 0;
        }
    else
#endif
        (void)snprintf(state->path, len + 1, "%s", (const char *)path);

    /* compute the flags for open() */
    oflag =
#ifdef O_LARGEFILE
        O_LARGEFILE |
#endif
#ifdef O_BINARY
        O_BINARY |
#endif
#ifdef O_CLOEXEC
        (cloexec ? O_CLOEXEC : 0) |
#endif
        (state->mode == GZ_READ ?
         O_RDONLY :
         (O_WRONLY | O_CREAT |
#ifdef O_EXCL
          (exclusive ? O_EXCL : 0) |
#endif
          (state->mode == GZ_WRITE ?
           O_TRUNC :
           O_APPEND)));

    /* open the file with the appropriate flags (or just use fd) */
    state->fd = fd > -1 ? fd : (
#if defined(_WIN32)
        fd == -2 ? _wopen((const wchar_t *)path, oflag, 0666) :
#elif __CYGWIN__
        fd == -2 ? open(state->path, oflag, 0666) :
#endif
        open((const char *)path, oflag, 0666));
    if (state->fd == -1) {
        free(state->path);
        gz_state_free(state);
        return NULL;
    }
    if (state->mode == GZ_APPEND) {
        LSEEK(state->fd, 0, SEEK_END);  /* so gzoffset() is correct */
        state->mode = GZ_WRITE;         /* simplify later checks */
    }

    /* save the current position for rewinding (only if reading) */
    if (state->mode == GZ_READ) {
        state->start = LSEEK(state->fd, 0, SEEK_CUR);
        if (state->start == -1) state->start = 0;
    }

    /* initialize stream */
    gz_reset(state);

    /* return stream */
    return (gzFile)state;
}

/* -- see zlib.h -- */
gzFile Z_EXPORT PREFIX(gzopen)(const char *path, const char *mode) {
    return gz_open(path, -1, mode);
}

#ifdef ZLIB_COMPAT
gzFile Z_EXPORT PREFIX4(gzopen)(const char *path, const char *mode) {
    return gz_open(path, -1, mode);
}
#endif

/* -- see zlib.h -- */
gzFile Z_EXPORT PREFIX(gzdopen)(int fd, const char *mode) {
    gzFile gz;
    char path[32];         /* identifier for error messages */

    if (fd == -1)
        return NULL;
    (void)snprintf(path, 32, "<fd:%d>", fd); /* for debugging */
    gz = gz_open(path, fd, mode);
    return gz;
}

/* -- see zlib.h -- */
#ifdef WIDECHAR
gzFile Z_EXPORT PREFIX(gzopen_w)(const wchar_t *path, const char *mode) {
    return gz_open(path, -2, mode);
}
#endif

z_int32_t Z_EXPORT PREFIX(gzclose)(gzFile file) {
#ifndef NO_GZCOMPRESS
    gz_state *state;

    if (file == NULL)
        return Z_STREAM_ERROR;
    state = (gz_state *)file;

    return state->mode == GZ_READ ? PREFIX(gzclose_r)(file) : PREFIX(gzclose_w)(file);
#else
    return PREFIX(gzclose_r)(file);
#endif
}

/* -- see zlib.h -- */
z_int32_t Z_EXPORT PREFIX(gzbuffer)(gzFile file, z_uint32_t size) {
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return -1;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return -1;

    /* make sure we haven't already allocated memory */
    if (state->size != 0)
        return -1;

    /* check and set requested size */
    if ((size << 1) < size)
        return -1;              /* need to be able to double it */
    if (size < 8)
        size = 8;               /* needed to behave well with flushing */
    state->want = size;
    return 0;
}

/* -- see zlib.h -- */
z_int32_t Z_EXPORT PREFIX(gzrewind)(gzFile file) {
    gz_state *state;

    /* get internal structure */
    if (file == NULL)
        return -1;
    state = (gz_state *)file;

    /* check that we're reading and that there's no error */
    if (state->mode != GZ_READ || (state->err != Z_OK && state->err != Z_BUF_ERROR))
        return -1;

    /* back up and start over */
    if (LSEEK(state->fd, state->start, SEEK_SET) == -1)
        return -1;
    gz_reset(state);
    return 0;
}

/* -- see zlib.h -- */
z_off64_t Z_EXPORT PREFIX4(gzseek)(gzFile file, z_off64_t offset, int whence) {
    unsigned n;
    z_off64_t ret;
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return -1;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return -1;

    /* check that there's no error */
    if (state->err != Z_OK && state->err != Z_BUF_ERROR)
        return -1;

    /* can only seek from start or relative to current position */
    if (whence != SEEK_SET && whence != SEEK_CUR)
        return -1;

    /* normalize offset to a SEEK_CUR specification */
    if (whence == SEEK_SET)
        offset -= state->x.pos;
    else if (state->seek)
        offset += state->skip;
    state->seek = 0;

    /* if within raw area while reading, just go there */
    if (state->mode == GZ_READ && state->how == COPY && state->x.pos + offset >= 0) {
        ret = LSEEK(state->fd, offset - (z_off64_t)state->x.have, SEEK_CUR);
        if (ret == -1)
            return -1;
        state->x.have = 0;
        state->eof = 0;
        state->past = 0;
        state->seek = 0;
        gz_error(state, Z_OK, NULL);
        state->strm.avail_in = 0;
        state->x.pos += offset;
        return state->x.pos;
    }

    /* calculate skip amount, rewinding if needed for back seek when reading */
    if (offset < 0) {
        if (state->mode != GZ_READ)         /* writing -- can't go backwards */
            return -1;
        offset += state->x.pos;
        if (offset < 0)                     /* before start of file! */
            return -1;
        if (PREFIX(gzrewind)(file) == -1)   /* rewind, then skip to offset */
            return -1;
    }

    /* if reading, skip what's in output buffer (one less gzgetc() check) */
    if (state->mode == GZ_READ) {
        n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > offset ? (unsigned)offset : state->x.have;
        state->x.have -= n;
        state->x.next += n;
        state->x.pos += n;
        offset -= n;
    }

    /* request skip (if not zero) */
    if (offset) {
        state->seek = 1;
        state->skip = offset;
    }
    return state->x.pos + offset;
}

/* -- see zlib.h -- */
#ifdef ZLIB_COMPAT
z_off_t Z_EXPORT PREFIX(gzseek)(gzFile file, z_off_t offset, int whence) {
    z_off64_t ret;

    ret = PREFIX4(gzseek)(file, (z_off64_t)offset, whence);
    return ret == (z_off_t)ret ? (z_off_t)ret : -1;
}
#endif

/* -- see zlib.h -- */
z_off64_t Z_EXPORT PREFIX4(gztell)(gzFile file) {
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return -1;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return -1;

    /* return position */
    return state->x.pos + (state->seek ? state->skip : 0);
}

/* -- see zlib.h -- */
#ifdef ZLIB_COMPAT
z_off_t Z_EXPORT PREFIX(gztell)(gzFile file) {

    z_off64_t ret;

    ret = PREFIX4(gztell)(file);
    return ret == (z_off_t)ret ? (z_off_t)ret : -1;
}
#endif

/* -- see zlib.h -- */
z_off64_t Z_EXPORT PREFIX4(gzoffset)(gzFile file) {
    z_off64_t offset;
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return -1;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return -1;

    /* compute and return effective offset in file */
    offset = LSEEK(state->fd, 0, SEEK_CUR);
    if (offset == -1)
        return -1;
    if (state->mode == GZ_READ)             /* reading */
        offset -= state->strm.avail_in;     /* don't count buffered input */
    return offset;
}

/* -- see zlib.h -- */
#ifdef ZLIB_COMPAT
z_off_t Z_EXPORT PREFIX(gzoffset)(gzFile file) {
    z_off64_t ret;

    ret = PREFIX4(gzoffset)(file);
    return ret == (z_off_t)ret ? (z_off_t)ret : -1;
}
#endif

/* -- see zlib.h -- */
z_int32_t Z_EXPORT PREFIX(gzeof)(gzFile file) {
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return 0;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return 0;

    /* return end-of-file state */
    return state->mode == GZ_READ ? state->past : 0;
}

/* -- see zlib.h -- */
const char * Z_EXPORT PREFIX(gzerror)(gzFile file, z_int32_t *errnum) {
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return NULL;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return NULL;

    /* return error information */
    if (errnum != NULL)
        *errnum = state->err;
    return state->err == Z_MEM_ERROR ? "out of memory" : (state->msg == NULL ? "" : state->msg);
}

/* -- see zlib.h -- */
void Z_EXPORT PREFIX(gzclearerr)(gzFile file) {
    gz_state *state;

    /* get internal structure and check integrity */
    if (file == NULL)
        return;
    state = (gz_state *)file;
    if (state->mode != GZ_READ && state->mode != GZ_WRITE)
        return;

    /* clear error and end-of-file */
    if (state->mode == GZ_READ) {
        state->eof = 0;
        state->past = 0;
    }
    gz_error(state, Z_OK, NULL);
}

/* Create an error message in allocated memory and set state->err and
   state->msg accordingly.  Free any previous error message already there.  Do
   not try to free or allocate space if the error is Z_MEM_ERROR (out of
   memory).  Simply save the error message as a static string.  If there is an
   allocation failure constructing the error message, then convert the error to
   out of memory. */
void Z_INTERNAL gz_error(gz_state *state, int err, const char *msg) {
    /* free previously allocated message and clear */
    if (state->msg != NULL) {
        if (state->err != Z_MEM_ERROR)
            free(state->msg);
        state->msg = NULL;
    }

    /* if fatal, set state->x.have to 0 so that the gzgetc() macro fails */
    if (err != Z_OK && err != Z_BUF_ERROR)
        state->x.have = 0;

    /* set error code, and if no message, then done */
    state->err = err;
    if (msg == NULL)
        return;

    /* for an out of memory error, return literal string when requested */
    if (err == Z_MEM_ERROR)
        return;

    /* construct error message with path */
    if ((state->msg = (char *)malloc(strlen(state->path) + strlen(msg) + 3)) == NULL) {
        state->err = Z_MEM_ERROR;
        return;
    }
    (void)snprintf(state->msg, strlen(state->path) + strlen(msg) + 3, "%s%s%s", state->path, ": ", msg);
}

#ifdef ZLIB_COMPAT
unsigned Z_INTERNAL gz_intmax(void) {
    return INT_MAX;
}
#endif

Coverage Report

Created: 2025-11-06 06:16

Line	Count	Source
1		/* gzlib.c -- zlib functions common to reading and writing gzip files
2		* Copyright (C) 2004-2024 Mark Adler
3		* For conditions of distribution and use, see copyright notice in zlib.h
4		*/
5
6		#include "zbuild.h"
7		#include "zutil.h"
8		#include "zutil_p.h"
9		#include "gzguts.h"
10
11		#if defined(_WIN32)
12		# define LSEEK _lseeki64
13		#else
14		#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
15	6.10k	# define LSEEK lseek64
16		#else
17		# define LSEEK lseek
18		#endif
19		#endif
20
21		/* Local functions */
22		static gzFile gz_state_init(void);
23		static void gz_reset(gz_state *);
24		static gzFile gz_open(const void , int, const char );
25
26		/* Initialize struct for gzFile state */
27	12.2k	static gzFile gz_state_init(void) {
28		/* allocate gzFile structure to return */
29	12.2k	gz_state state = (gz_state )zng_alloc(sizeof(gz_state));
30	12.2k	if (state == NULL)
31	0	return NULL;
32
33	12.2k	state->strm.zalloc = NULL;
34	12.2k	state->strm.zfree = NULL;
35	12.2k	state->strm.opaque = NULL;
36	12.2k	state->strm.next_in = NULL;
37
38	12.2k	state->size = 0;
39	12.2k	state->want = GZBUFSIZE;
40	12.2k	state->in = NULL;
41	12.2k	state->out = NULL;
42	12.2k	state->direct = 0;
43	12.2k	state->mode = GZ_NONE;
44	12.2k	state->level = Z_DEFAULT_COMPRESSION;
45	12.2k	state->strategy = Z_DEFAULT_STRATEGY;
46	12.2k	state->msg = NULL;
47	12.2k	return (gzFile)state;
48	12.2k	}
49
50	6.11k	void Z_INTERNAL gz_state_free(gz_state *state) {
51	6.11k	zng_free(state);
52	6.11k	}
53
54		/* Reset gzip file state */
55	12.2k	static void gz_reset(gz_state *state) {
56	12.2k	state->x.have = 0; /* no output data available */
57	12.2k	if (state->mode == GZ_READ) { /* for reading ... */
58	6.10k	state->eof = 0; /* not at end of file */
59	6.10k	state->past = 0; /* have not read past end yet */
60	6.10k	state->how = LOOK; /* look for gzip header */
61	6.10k	}
62	6.11k	else /* for writing ... */
63	6.11k	state->reset = 0; /* no deflateReset pending */
64	12.2k	state->seek = 0; /* no seek request pending */
65	12.2k	gz_error(state, Z_OK, NULL); /* clear error */
66	12.2k	state->x.pos = 0; /* no uncompressed data yet */
67	12.2k	state->strm.avail_in = 0; /* no input data yet */
68	12.2k	}
69
70		/* Allocate in/out buffers for gzFile */
71	12.2k	int Z_INTERNAL gz_buffer_alloc(gz_state *state) {
72	12.2k	int want = state->want;
73	12.2k	int in_size = want, out_size = want;
74
75	12.2k	if (state->mode == GZ_WRITE) {
76	6.11k	in_size = want * 2; // double input buffer for compression (ref: gzprintf)
77	6.11k	if (state->direct)
78	5	out_size = 0; // output buffer not needed in write + direct mode
79	6.11k	} else if (state->mode == GZ_READ) {
80	6.10k	out_size = want * 2; // double output buffer for decompression
81	6.10k	}
82
83	12.2k	state->buffers = (unsigned char *)zng_alloc_aligned((in_size + out_size), 64);
84	12.2k	state->in = state->buffers;
85	12.2k	if (out_size) {
86	12.2k	state->out = state->buffers + (in_size); // Outbuffer goes after inbuffer
87	12.2k	}
88
89		/* Return error if memory allocation failed */
90	12.2k	if (state->in == NULL \|\| (out_size && state->out == NULL)) {
91	0	gz_buffer_free(state);
92	0	gz_error(state, Z_MEM_ERROR, "out of memory");
93	0	return -1;
94	0	}
95
96	12.2k	state->size = want; // mark state as initialized
97	12.2k	return 0;
98	12.2k	}
99
100	12.2k	void Z_INTERNAL gz_buffer_free(gz_state *state) {
101	12.2k	zng_free_aligned(state->buffers);
102	12.2k	state->buffers = NULL;
103	12.2k	state->out = NULL;
104	12.2k	state->in = NULL;
105	12.2k	state->size = 0;
106	12.2k	}
107
108		/* Open a gzip file either by name or file descriptor. */
109	12.2k	static gzFile gz_open(const void path, int fd, const char mode) {
110	12.2k	gz_state *state;
111	12.2k	size_t len;
112	12.2k	int oflag;
113	12.2k	#ifdef O_CLOEXEC
114	12.2k	int cloexec = 0;
115	12.2k	#endif
116	12.2k	#ifdef O_EXCL
117	12.2k	int exclusive = 0;
118	12.2k	#endif
119
120		/* check input */
121	12.2k	if (path == NULL)
122	0	return NULL;
123
124		/* Initialize gzFile state */
125	12.2k	state = (gz_state *)gz_state_init();
126	12.2k	if (state == NULL)
127	0	return NULL;
128
129		/* interpret mode */
130	47.0k	while (*mode) {
131	34.8k	if (mode >= '0' && mode <= '9') {
132	6.11k	state->level = *mode - '0';
133	28.7k	} else {
134	28.7k	switch (*mode) {
135	6.10k	case 'r':
136	6.10k	state->mode = GZ_READ;
137	6.10k	break;
138	0	#ifndef NO_GZCOMPRESS
139	6.11k	case 'w':
140	6.11k	state->mode = GZ_WRITE;
141	6.11k	break;
142	0	case 'a':
143	0	state->mode = GZ_APPEND;
144	0	break;
145	0	#endif
146	0	case '+': /* can't read and write at the same time */
147	0	gz_state_free(state);
148	0	return NULL;
149	12.2k	case 'b': /* ignore -- will request binary anyway */
150	12.2k	break;
151	0	#ifdef O_CLOEXEC
152	0	case 'e':
153	0	cloexec = 1;
154	0	break;
155	0	#endif
156	0	#ifdef O_EXCL
157	0	case 'x':
158	0	exclusive = 1;
159	0	break;
160	0	#endif
161	992	case 'f':
162	992	state->strategy = Z_FILTERED;
163	992	break;
164	627	case 'h':
165	627	state->strategy = Z_HUFFMAN_ONLY;
166	627	break;
167	1.76k	case 'R':
168	1.76k	state->strategy = Z_RLE;
169	1.76k	break;
170	885	case 'F':
171	885	state->strategy = Z_FIXED;
172	885	break;
173	5	case 'T':
174	5	state->direct = 1;
175	5	break;
176	0	default: /* could consider as an error, but just ignore */
177	0	{}
178	28.7k	}
179	28.7k	}
180	34.8k	mode++;
181	34.8k	}
182
183		/* must provide an "r", "w", or "a" */
184	12.2k	if (state->mode == GZ_NONE) {
185	0	gz_state_free(state);
186	0	return NULL;
187	0	}
188
189		/* can't force transparent read */
190	12.2k	if (state->mode == GZ_READ) {
191	6.10k	if (state->direct) {
192	0	gz_state_free(state);
193	0	return NULL;
194	0	}
195	6.10k	state->direct = 1; /* for empty file */
196	6.10k	}
197
198		/* save the path name for error messages */
199		#ifdef WIDECHAR
200		if (fd == -2) {
201		len = wcstombs(NULL, (const wchar_t *)path, 0);
202		if (len == (size_t)-1)
203		len = 0;
204		} else
205		#endif
206	12.2k	len = strlen((const char *)path);
207	12.2k	state->path = (char *)malloc(len + 1);
208	12.2k	if (state->path == NULL) {
209	0	gz_state_free(state);
210	0	return NULL;
211	0	}
212		#ifdef WIDECHAR
213		if (fd == -2)
214		if (len) {
215		wcstombs(state->path, (const wchar_t *)path, len + 1);
216		} else {
217		*(state->path) = 0;
218		}
219		else
220		#endif
221	12.2k	(void)snprintf(state->path, len + 1, "%s", (const char *)path);
222
223		/* compute the flags for open() */
224	12.2k	oflag =
225	12.2k	#ifdef O_LARGEFILE
226	12.2k	O_LARGEFILE \|
227	12.2k	#endif
228		#ifdef O_BINARY
229		O_BINARY \|
230		#endif
231	12.2k	#ifdef O_CLOEXEC
232	12.2k	(cloexec ? O_CLOEXEC : 0) \|
233	12.2k	#endif
234	12.2k	(state->mode == GZ_READ ?
235	12.2k	O_RDONLY :
236	12.2k	(O_WRONLY \| O_CREAT \|
237	6.11k	#ifdef O_EXCL
238	6.11k	(exclusive ? O_EXCL : 0) \|
239	6.11k	#endif
240	6.11k	(state->mode == GZ_WRITE ?
241	6.11k	O_TRUNC :
242	6.11k	O_APPEND)));
243
244		/* open the file with the appropriate flags (or just use fd) */
245	12.2k	state->fd = fd > -1 ? fd : (
246		#if defined(_WIN32)
247		fd == -2 ? _wopen((const wchar_t *)path, oflag, 0666) :
248		#elif __CYGWIN__
249		fd == -2 ? open(state->path, oflag, 0666) :
250		#endif
251	12.2k	open((const char *)path, oflag, 0666));
252	12.2k	if (state->fd == -1) {
253	0	free(state->path);
254	0	gz_state_free(state);
255	0	return NULL;
256	0	}
257	12.2k	if (state->mode == GZ_APPEND) {
258	0	LSEEK(state->fd, 0, SEEK_END); /* so gzoffset() is correct */
259	0	state->mode = GZ_WRITE; /* simplify later checks */
260	0	}
261
262		/* save the current position for rewinding (only if reading) */
263	12.2k	if (state->mode == GZ_READ) {
264	6.10k	state->start = LSEEK(state->fd, 0, SEEK_CUR);
265	6.10k	if (state->start == -1) state->start = 0;
266	6.10k	}
267
268		/* initialize stream */
269	12.2k	gz_reset(state);
270
271		/* return stream */
272	12.2k	return (gzFile)state;
273	12.2k	}
274
275		/* -- see zlib.h -- */
276	12.2k	gzFile Z_EXPORT PREFIX(gzopen)(const char path, const char mode) {
277	12.2k	return gz_open(path, -1, mode);
278	12.2k	}
279
280		#ifdef ZLIB_COMPAT
281		gzFile Z_EXPORT PREFIX4(gzopen)(const char path, const char mode) {
282		return gz_open(path, -1, mode);
283		}
284		#endif
285
286		/* -- see zlib.h -- */
287	0	gzFile Z_EXPORT PREFIX(gzdopen)(int fd, const char *mode) {
288	0	gzFile gz;
289	0	char path[32]; /* identifier for error messages */
290
291	0	if (fd == -1)
292	0	return NULL;
293	0	(void)snprintf(path, 32, "<fd:%d>", fd); /* for debugging */
294	0	gz = gz_open(path, fd, mode);
295	0	return gz;
296	0	}
297
298		/* -- see zlib.h -- */
299		#ifdef WIDECHAR
300		gzFile Z_EXPORT PREFIX(gzopen_w)(const wchar_t path, const char mode) {
301		return gz_open(path, -2, mode);
302		}
303		#endif
304
305	12.2k	z_int32_t Z_EXPORT PREFIX(gzclose)(gzFile file) {
306	12.2k	#ifndef NO_GZCOMPRESS
307	12.2k	gz_state *state;
308
309	12.2k	if (file == NULL)
310	0	return Z_STREAM_ERROR;
311	12.2k	state = (gz_state *)file;
312
313	12.2k	return state->mode == GZ_READ ? PREFIX(gzclose_r)(file) : PREFIX(gzclose_w)(file);
314		#else
315		return PREFIX(gzclose_r)(file);
316		#endif
317	12.2k	}
318
319		/* -- see zlib.h -- */
320	0	z_int32_t Z_EXPORT PREFIX(gzbuffer)(gzFile file, z_uint32_t size) {
321	0	gz_state *state;
322
323		/* get internal structure and check integrity */
324	0	if (file == NULL)
325	0	return -1;
326	0	state = (gz_state *)file;
327	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
328	0	return -1;
329
330		/* make sure we haven't already allocated memory */
331	0	if (state->size != 0)
332	0	return -1;
333
334		/* check and set requested size */
335	0	if ((size << 1) < size)
336	0	return -1; /* need to be able to double it */
337	0	if (size < 8)
338	0	size = 8; /* needed to behave well with flushing */
339	0	state->want = size;
340	0	return 0;
341	0	}
342
343		/* -- see zlib.h -- */
344	0	z_int32_t Z_EXPORT PREFIX(gzrewind)(gzFile file) {
345	0	gz_state *state;
346
347		/* get internal structure */
348	0	if (file == NULL)
349	0	return -1;
350	0	state = (gz_state *)file;
351
352		/* check that we're reading and that there's no error */
353	0	if (state->mode != GZ_READ \|\| (state->err != Z_OK && state->err != Z_BUF_ERROR))
354	0	return -1;
355
356		/* back up and start over */
357	0	if (LSEEK(state->fd, state->start, SEEK_SET) == -1)
358	0	return -1;
359	0	gz_reset(state);
360	0	return 0;
361	0	}
362
363		/* -- see zlib.h -- */
364	0	z_off64_t Z_EXPORT PREFIX4(gzseek)(gzFile file, z_off64_t offset, int whence) {
365	0	unsigned n;
366	0	z_off64_t ret;
367	0	gz_state *state;
368
369		/* get internal structure and check integrity */
370	0	if (file == NULL)
371	0	return -1;
372	0	state = (gz_state *)file;
373	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
374	0	return -1;
375
376		/* check that there's no error */
377	0	if (state->err != Z_OK && state->err != Z_BUF_ERROR)
378	0	return -1;
379
380		/* can only seek from start or relative to current position */
381	0	if (whence != SEEK_SET && whence != SEEK_CUR)
382	0	return -1;
383
384		/* normalize offset to a SEEK_CUR specification */
385	0	if (whence == SEEK_SET)
386	0	offset -= state->x.pos;
387	0	else if (state->seek)
388	0	offset += state->skip;
389	0	state->seek = 0;
390
391		/* if within raw area while reading, just go there */
392	0	if (state->mode == GZ_READ && state->how == COPY && state->x.pos + offset >= 0) {
393	0	ret = LSEEK(state->fd, offset - (z_off64_t)state->x.have, SEEK_CUR);
394	0	if (ret == -1)
395	0	return -1;
396	0	state->x.have = 0;
397	0	state->eof = 0;
398	0	state->past = 0;
399	0	state->seek = 0;
400	0	gz_error(state, Z_OK, NULL);
401	0	state->strm.avail_in = 0;
402	0	state->x.pos += offset;
403	0	return state->x.pos;
404	0	}
405
406		/* calculate skip amount, rewinding if needed for back seek when reading */
407	0	if (offset < 0) {
408	0	if (state->mode != GZ_READ) /* writing -- can't go backwards */
409	0	return -1;
410	0	offset += state->x.pos;
411	0	if (offset < 0) /* before start of file! */
412	0	return -1;
413	0	if (PREFIX(gzrewind)(file) == -1) /* rewind, then skip to offset */
414	0	return -1;
415	0	}
416
417		/* if reading, skip what's in output buffer (one less gzgetc() check) */
418	0	if (state->mode == GZ_READ) {
419	0	n = GT_OFF(state->x.have) \|\| (z_off64_t)state->x.have > offset ? (unsigned)offset : state->x.have;
420	0	state->x.have -= n;
421	0	state->x.next += n;
422	0	state->x.pos += n;
423	0	offset -= n;
424	0	}
425
426		/* request skip (if not zero) */
427	0	if (offset) {
428	0	state->seek = 1;
429	0	state->skip = offset;
430	0	}
431	0	return state->x.pos + offset;
432	0	}
433
434		/* -- see zlib.h -- */
435		#ifdef ZLIB_COMPAT
436		z_off_t Z_EXPORT PREFIX(gzseek)(gzFile file, z_off_t offset, int whence) {
437		z_off64_t ret;
438
439		ret = PREFIX4(gzseek)(file, (z_off64_t)offset, whence);
440		return ret == (z_off_t)ret ? (z_off_t)ret : -1;
441		}
442		#endif
443
444		/* -- see zlib.h -- */
445	0	z_off64_t Z_EXPORT PREFIX4(gztell)(gzFile file) {
446	0	gz_state *state;
447
448		/* get internal structure and check integrity */
449	0	if (file == NULL)
450	0	return -1;
451	0	state = (gz_state *)file;
452	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
453	0	return -1;
454
455		/* return position */
456	0	return state->x.pos + (state->seek ? state->skip : 0);
457	0	}
458
459		/* -- see zlib.h -- */
460		#ifdef ZLIB_COMPAT
461		z_off_t Z_EXPORT PREFIX(gztell)(gzFile file) {
462
463		z_off64_t ret;
464
465		ret = PREFIX4(gztell)(file);
466		return ret == (z_off_t)ret ? (z_off_t)ret : -1;
467		}
468		#endif
469
470		/* -- see zlib.h -- */
471	0	z_off64_t Z_EXPORT PREFIX4(gzoffset)(gzFile file) {
472	0	z_off64_t offset;
473	0	gz_state *state;
474
475		/* get internal structure and check integrity */
476	0	if (file == NULL)
477	0	return -1;
478	0	state = (gz_state *)file;
479	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
480	0	return -1;
481
482		/* compute and return effective offset in file */
483	0	offset = LSEEK(state->fd, 0, SEEK_CUR);
484	0	if (offset == -1)
485	0	return -1;
486	0	if (state->mode == GZ_READ) /* reading */
487	0	offset -= state->strm.avail_in; /* don't count buffered input */
488	0	return offset;
489	0	}
490
491		/* -- see zlib.h -- */
492		#ifdef ZLIB_COMPAT
493		z_off_t Z_EXPORT PREFIX(gzoffset)(gzFile file) {
494		z_off64_t ret;
495
496		ret = PREFIX4(gzoffset)(file);
497		return ret == (z_off_t)ret ? (z_off_t)ret : -1;
498		}
499		#endif
500
501		/* -- see zlib.h -- */
502	0	z_int32_t Z_EXPORT PREFIX(gzeof)(gzFile file) {
503	0	gz_state *state;
504
505		/* get internal structure and check integrity */
506	0	if (file == NULL)
507	0	return 0;
508	0	state = (gz_state *)file;
509	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
510	0	return 0;
511
512		/* return end-of-file state */
513	0	return state->mode == GZ_READ ? state->past : 0;
514	0	}
515
516		/* -- see zlib.h -- */
517	0	const char * Z_EXPORT PREFIX(gzerror)(gzFile file, z_int32_t *errnum) {
518	0	gz_state *state;
519
520		/* get internal structure and check integrity */
521	0	if (file == NULL)
522	0	return NULL;
523	0	state = (gz_state *)file;
524	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
525	0	return NULL;
526
527		/* return error information */
528	0	if (errnum != NULL)
529	0	*errnum = state->err;
530	0	return state->err == Z_MEM_ERROR ? "out of memory" : (state->msg == NULL ? "" : state->msg);
531	0	}
532
533		/* -- see zlib.h -- */
534	0	void Z_EXPORT PREFIX(gzclearerr)(gzFile file) {
535	0	gz_state *state;
536
537		/* get internal structure and check integrity */
538	0	if (file == NULL)
539	0	return;
540	0	state = (gz_state *)file;
541	0	if (state->mode != GZ_READ && state->mode != GZ_WRITE)
542	0	return;
543
544		/* clear error and end-of-file */
545	0	if (state->mode == GZ_READ) {
546	0	state->eof = 0;
547	0	state->past = 0;
548	0	}
549	0	gz_error(state, Z_OK, NULL);
550	0	}
551
552		/* Create an error message in allocated memory and set state->err and
553		state->msg accordingly. Free any previous error message already there. Do
554		not try to free or allocate space if the error is Z_MEM_ERROR (out of
555		memory). Simply save the error message as a static string. If there is an
556		allocation failure constructing the error message, then convert the error to
557		out of memory. */
558	24.4k	void Z_INTERNAL gz_error(gz_state state, int err, const char msg) {
559		/* free previously allocated message and clear */
560	24.4k	if (state->msg != NULL) {
561	0	if (state->err != Z_MEM_ERROR)
562	0	free(state->msg);
563	0	state->msg = NULL;
564	0	}
565
566		/* if fatal, set state->x.have to 0 so that the gzgetc() macro fails */
567	24.4k	if (err != Z_OK && err != Z_BUF_ERROR)
568	0	state->x.have = 0;
569
570		/* set error code, and if no message, then done */
571	24.4k	state->err = err;
572	24.4k	if (msg == NULL)
573	24.4k	return;
574
575		/* for an out of memory error, return literal string when requested */
576	0	if (err == Z_MEM_ERROR)
577	0	return;
578
579		/* construct error message with path */
580	0	if ((state->msg = (char *)malloc(strlen(state->path) + strlen(msg) + 3)) == NULL) {
581	0	state->err = Z_MEM_ERROR;
582	0	return;
583	0	}
584	0	(void)snprintf(state->msg, strlen(state->path) + strlen(msg) + 3, "%s%s%s", state->path, ": ", msg);
585	0	}
586
587		#ifdef ZLIB_COMPAT
588		unsigned Z_INTERNAL gz_intmax(void) {
589		return INT_MAX;
590		}
591		#endif