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Diffstat (limited to 'lib/compression.c')
| -rw-r--r-- | lib/compression.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/lib/compression.c b/lib/compression.c new file mode 100644 index 0000000..fe4696c --- /dev/null +++ b/lib/compression.c @@ -0,0 +1,195 @@ +/* + * compression.c: code to find decompressor / compression extension + * + * Copyright (C) 1994, 1995 Graeme W. Wilford. (Wilf.) + * Copyright (C) 2001-2022 Colin Watson. + * + * This file is part of man-db. + * + * man-db is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * man-db is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with man-db; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Sat Aug 20 15:01:02 BST 1994 Wilf. (G.Wilford@ee.surrey.ac.uk) + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif /* HAVE_CONFIG_H */ + +#include <assert.h> +#include <stdbool.h> +#include <stdio.h> +#include <errno.h> +#include <signal.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "error.h" +#include "xstrndup.h" +#include "xvasprintf.h" + +#include "manconfig.h" + +#include "appendstr.h" +#include "compression.h" + +/*--------------------------------------------------------------------------*/ +/* This is where we define the decompressors used to decompress any nroff */ +/* source that we find. All cat pages are compressed with either gzip (if */ +/* available) or compress. This is not the place to define _the_ cat page */ +/* decompressor - see ./manconfig.h for that. */ +/* */ +/* To add a decompressor all you need to know is its name (preferrably its */ +/* location), and the unique extension that it gives to files compressed */ +/* with it. Here is an example. You have a compressor named foobar and */ +/* compressed files have an extension of .fb . It is located in /usr/bin */ +/* and requires a -d option to be used as a decompressor. Add the following */ +/* line to the structure below. */ +/* */ +/* {"/usr/bin/foobar -d", "fb", NULL}, */ +/*--------------------------------------------------------------------------*/ + +struct compression comp_list[] = { + +/* If we have gzip, incorporate the following */ +#ifdef HAVE_GZIP + {PROG_GUNZIP, "gz", NULL}, + {PROG_GUNZIP, "z", NULL}, +#endif /* HAVE_GZIP */ + +/* If we have compress, incorporate the following */ +#ifdef HAVE_COMPRESS + {PROG_UNCOMPRESS, "Z", NULL}, +/* Else if we have gzip, incorporate the following */ +#elif defined (HAVE_GZIP) + {PROG_GUNZIP, "Z", NULL}, +#endif /* HAVE_COMPRESS || HAVE_GZIP */ + +/* If we have bzip2, incorporate the following */ +#ifdef HAVE_BZIP2 + {PROG_BUNZIP2, "bz2", NULL}, +#endif /* HAVE_BZIP2 */ + +/* If we have xz, incorporate the following */ +#ifdef HAVE_XZ + {PROG_UNXZ, "xz", NULL}, + {PROG_UNXZ, "lzma", NULL}, +/* Else if we have lzma, incorporate the following */ +#elif defined (HAVE_LZMA) + {PROG_UNLZMA, "lzma", NULL}, +#endif /* HAVE_XZ || HAVE_LZMA */ + +/* If we have lzip, incorporate the following */ +#ifdef HAVE_LZIP + {PROG_UNLZIP, "lz", NULL}, +#endif /* HAVE_LZIP */ + +/* If we have zstd, incorporate the following */ +#ifdef HAVE_ZSTD + {PROG_UNZSTD, "zst", NULL}, + {PROG_UNZSTD, "zstd", NULL}, +#endif /* HAVE_ZSTD */ + +/*------------------------------------------------------*/ +/* Add your decompressor(s) and extension(s) below here */ +/*------------------------------------------------------*/ + +/*----------------*/ +/* and above here */ +/*----------------*/ + +/* ... and the last structure is */ + {NULL, NULL, NULL} +}; + +/* Take filename as arg, return structure containing decompressor + and extension, or NULL if no comp extension found. + If want_stem, set comp->stem to the filename without extension, which + the caller should free. + + eg. + filename = /usr/man/man1/foo.1.gz + + comp->prog = "/usr/bin/gzip -dc"; + comp->ext = "gz"; + comp->stem = "/usr/man/man1/foo.1"; + */ +struct compression *comp_info (const char *filename, bool want_stem) +{ + const char *ext; + static struct compression hpux_comp = + {PROG_GUNZIP " -S \"\"", "", NULL}; + + ext = strrchr (filename, '.'); + + if (ext) { + struct compression *comp; + for (comp = comp_list; comp->ext; comp++) { + if (strcmp (comp->ext, ext + 1) == 0) { + if (want_stem) + comp->stem = xstrndup (filename, + ext - filename); + else + comp->stem = NULL; + return comp; + } + } + } + + if (*PROG_GUNZIP) { + ext = strstr (filename, ".Z/"); + if (ext) { + if (want_stem) + hpux_comp.stem = xstrndup (filename, + ext - filename); + else + hpux_comp.stem = NULL; + return &hpux_comp; + } + } + + return NULL; +} + +/* take filename w/o comp ext. as arg, return comp->stem as a relative + compressed file or NULL if none found */ +struct compression *comp_file (const char *filename) +{ + size_t len; + char *compfile; + struct compression *comp; + + compfile = xasprintf ("%s.", filename); + assert (compfile); + len = strlen (compfile); + + for (comp = comp_list; comp->ext; comp++) { + struct stat buf; + + compfile = appendstr (compfile, comp->ext, (void *) 0); + + if (stat (compfile, &buf) == 0) { + comp->stem = compfile; + return comp; + } + + *(compfile + len) = '\0'; + } + free (compfile); + return NULL; +} |