summaryrefslogtreecommitdiff
path: root/gs/base/gpmisc.c
diff options
context:
space:
mode:
Diffstat (limited to 'gs/base/gpmisc.c')
-rw-r--r--gs/base/gpmisc.c404
1 files changed, 404 insertions, 0 deletions
diff --git a/gs/base/gpmisc.c b/gs/base/gpmisc.c
new file mode 100644
index 000000000..e33f26478
--- /dev/null
+++ b/gs/base/gpmisc.c
@@ -0,0 +1,404 @@
+/* Copyright (C) 2001-2006 Artifex Software, Inc.
+ All Rights Reserved.
+
+ This software is provided AS-IS with no warranty, either express or
+ implied.
+
+ This software is distributed under license and may not be copied, modified
+ or distributed except as expressly authorized under the terms of that
+ license. Refer to licensing information at http://www.artifex.com/
+ or contact Artifex Software, Inc., 7 Mt. Lassen Drive - Suite A-134,
+ San Rafael, CA 94903, U.S.A., +1(415)492-9861, for further information.
+*/
+
+/* $Id$ */
+/* Miscellaneous support for platform facilities */
+
+#include "unistd_.h"
+#include "fcntl_.h"
+#include "stdio_.h"
+#include "stat_.h"
+#include "memory_.h"
+#include "string_.h"
+#include "gp.h"
+#include "gpgetenv.h"
+#include "gpmisc.h"
+
+/*
+ * Get the name of the directory for temporary files, if any. Currently
+ * this checks the TMPDIR and TEMP environment variables, in that order.
+ * The return value and the setting of *ptr and *plen are as for gp_getenv.
+ */
+int
+gp_gettmpdir(char *ptr, int *plen)
+{
+ int max_len = *plen;
+ int code = gp_getenv("TMPDIR", ptr, plen);
+
+ if (code != 1)
+ return code;
+ *plen = max_len;
+ return gp_getenv("TEMP", ptr, plen);
+}
+
+/*
+ * Open a temporary file, using O_EXCL and S_I*USR to prevent race
+ * conditions and symlink attacks.
+ */
+static FILE *
+gp_fopentemp_generic(const char *fname, const char *mode, bool b64)
+{
+ int flags = O_EXCL;
+ /* Scan the mode to construct the flags. */
+ const char *p = mode;
+ int fildes;
+ FILE *file;
+
+#if defined (O_LARGEFILE)
+ /* It works for Linux/gcc. */
+ if (b64)
+ flags |= O_LARGEFILE;
+#else
+ /* fixme : Not sure what to do. Unimplemented. */
+ /* MSVC has no O_LARGEFILE, but MSVC build never calls this function. */
+#endif
+ while (*p)
+ switch (*p++) {
+ case 'a':
+ flags |= O_CREAT | O_APPEND;
+ break;
+ case 'r':
+ flags |= O_RDONLY;
+ break;
+ case 'w':
+ flags |= O_CREAT | O_WRONLY | O_TRUNC;
+ break;
+#ifdef O_BINARY
+ /* Watcom C insists on this non-ANSI flag being set. */
+ case 'b':
+ flags |= O_BINARY;
+ break;
+#endif
+ case '+':
+ flags = (flags & ~(O_RDONLY | O_WRONLY)) | O_RDWR;
+ break;
+ default: /* e.g., 'b' */
+ break;
+ }
+ fildes = open(fname, flags, S_IRUSR | S_IWUSR);
+ if (fildes < 0)
+ return 0;
+ /*
+ * The DEC VMS C compiler incorrectly defines the second argument of
+ * fdopen as (char *), rather than following the POSIX.1 standard,
+ * which defines it as (const char *). Patch this here.
+ */
+ file = fdopen(fildes, (char *)mode); /* still really const */
+ if (file == 0)
+ close(fildes);
+ return file;
+}
+
+FILE *gp_fopentemp_64(const char *fname, const char *mode)
+{
+ return gp_fopentemp_generic(fname, mode, true);
+}
+
+FILE *gp_fopentemp(const char *fname, const char *mode)
+{
+ return gp_fopentemp_generic(fname, mode, false);
+}
+
+/* Append a string to buffer. */
+static inline bool
+append(char **bp, const char *bpe, const char **ip, uint len)
+{
+ if (bpe - *bp < len)
+ return false;
+ memcpy(*bp, *ip, len);
+ *bp += len;
+ *ip += len;
+ return true;
+}
+
+/* Search a separator forward. */
+static inline uint
+search_separator(const char **ip, const char *ipe, const char *item, int direction)
+{ uint slen = 0;
+ for (slen = 0; (*ip - ipe) * direction < 0; (*ip) += direction)
+ if((slen = gs_file_name_check_separator(*ip, ipe - *ip, item)) != 0)
+ break;
+ return slen;
+}
+
+
+/*
+ * Combine a file name with a prefix.
+ * Concatenates two paths and reduce parent references and current
+ * directory references from the concatenation when possible.
+ * The trailing zero byte is being added.
+ *
+ * Returns "gp_combine_success" if OK and sets '*blen' to the length of
+ * the combined string. If the combined string is too small for the buffer
+ * length passed in (as defined by the initial value of *blen), then the
+ * "gp_combine_small_buffer" code is returned.
+ *
+ * Also tolerates/skips leading IODevice specifiers such as %os% or %rom%
+ * When there is a leading '%' in the 'fname' no other processing is done.
+ *
+ * Examples :
+ * "/gs/lib" + "../Resource/CMap/H" --> "/gs/Resource/CMap/H"
+ * "C:/gs/lib" + "../Resource/CMap/H" --> "C:/gs/Resource/CMap/H"
+ * "hard disk:gs:lib" + "::Resource:CMap:H" -->
+ * "hard disk:gs:Resource:CMap:H"
+ * "DUA1:[GHOSTSCRIPT.LIB" + "-.RESOURCE.CMAP]H" -->
+ * "DUA1:[GHOSTSCRIPT.RESOURCE.CMAP]H"
+ * "\\server\share/a/b///c/../d.e/./" + "../x.e/././/../../y.z/v.v" -->
+ * "\\server\share/a/y.z/v.v"
+ * "%rom%lib/" + "gs_init.ps" --> "%rom%lib/gs_init.ps
+ * "" + "%rom%lib/gs_init.ps" --> "%rom%lib/gs_init.ps"
+ */
+gp_file_name_combine_result
+gp_file_name_combine_generic(const char *prefix, uint plen, const char *fname, uint flen,
+ bool no_sibling, char *buffer, uint *blen)
+{
+ /*
+ * THIS CODE IS SHARED FOR MULTIPLE PLATFORMS.
+ * PLEASE DON'T CHANGE IT FOR A SPECIFIC PLATFORM.
+ * Change gp_file_name_combine instead.
+ */
+ char *bp = buffer, *bpe = buffer + *blen;
+ const char *ip, *ipe;
+ uint slen;
+ uint infix_type = 0; /* 0=none, 1=current, 2=parent. */
+ uint infix_len = 0;
+ uint rlen = gp_file_name_root(fname, flen);
+ /* We need a special handling of infixes only immediately after a drive. */
+
+ if ( flen > 0 && fname[0] == '%') {
+ /* IoDevice -- just return the fname as-is since this */
+ /* function only handles the default file system */
+ /* NOTE: %os% will subvert the normal processing of prefix and fname */
+ ip = fname;
+ *blen = flen;
+ if (!append(&bp, bpe, &ip, flen))
+ return gp_combine_small_buffer;
+ return gp_combine_success;
+ }
+ if (rlen != 0) {
+ /* 'fname' is absolute, ignore the prefix. */
+ ip = fname;
+ ipe = fname + flen;
+ } else {
+ /* Concatenate with prefix. */
+ ip = prefix;
+ ipe = prefix + plen;
+ rlen = gp_file_name_root(prefix, plen);
+ }
+ if (!append(&bp, bpe, &ip, rlen))
+ return gp_combine_small_buffer;
+ slen = gs_file_name_check_separator(bp, buffer - bp, bp); /* Backward search. */
+ if (rlen != 0 && slen == 0) {
+ /* Patch it against names like "c:dir" on Windows. */
+ const char *sep = gp_file_name_directory_separator();
+
+ slen = strlen(sep);
+ if (!append(&bp, bpe, &sep, slen))
+ return gp_combine_small_buffer;
+ rlen += slen;
+ }
+ for (;;) {
+ const char *item = ip;
+ uint ilen;
+
+ slen = search_separator(&ip, ipe, item, 1);
+ ilen = ip - item;
+ if (ilen == 0 && !gp_file_name_is_empty_item_meanful()) {
+ ip += slen;
+ slen = 0;
+ } else if (gp_file_name_is_current(item, ilen)) {
+ /* Skip the reference to 'current', except the starting one.
+ * We keep the starting 'current' for platforms, which
+ * require relative paths to start with it.
+ */
+ if (bp == buffer) {
+ if (!append(&bp, bpe, &item, ilen))
+ return gp_combine_small_buffer;
+ infix_type = 1;
+ infix_len = ilen;
+ } else {
+ ip += slen;
+ slen = 0;
+ }
+ } else if (!gp_file_name_is_parent(item, ilen)) {
+ if (!append(&bp, bpe, &item, ilen))
+ return gp_combine_small_buffer;
+ /* The 'item' pointer is now broken; it may be restored using 'ilen'. */
+ } else if (bp == buffer + rlen + infix_len) {
+ /* Input is a parent and the output only contains a root and an infix. */
+ if (rlen != 0)
+ return gp_combine_cant_handle;
+ switch (infix_type) {
+ case 1:
+ /* Replace the infix with parent. */
+ bp = buffer + rlen; /* Drop the old infix, if any. */
+ infix_len = 0;
+ /* Falls through. */
+ case 0:
+ /* We have no infix, start with parent. */
+ if ((no_sibling && ipe == fname + flen && flen != 0) ||
+ !gp_file_name_is_partent_allowed())
+ return gp_combine_cant_handle;
+ /* Falls through. */
+ case 2:
+ /* Append one more parent - falls through. */
+ DO_NOTHING;
+ }
+ if (!append(&bp, bpe, &item, ilen))
+ return gp_combine_small_buffer;
+ infix_type = 2;
+ infix_len += ilen;
+ /* Recompute the separator length. We cannot use the old slen on Mac OS. */
+ slen = gs_file_name_check_separator(ip, ipe - ip, ip);
+ } else {
+ /* Input is a parent and the output continues after infix. */
+ /* Unappend the last separator and the last item. */
+ uint slen1 = gs_file_name_check_separator(bp, buffer + rlen - bp, bp); /* Backward search. */
+ char *bie = bp - slen1;
+
+ bp = bie;
+ DISCARD(search_separator((const char **)&bp, buffer + rlen, bp, -1));
+ /* The cast above quiets a gcc warning. We believe it's a bug in the compiler. */
+ /* Skip the input with separator. We cannot use slen on Mac OS. */
+ ip += gs_file_name_check_separator(ip, ipe - ip, ip);
+ if (no_sibling) {
+ const char *p = ip;
+
+ DISCARD(search_separator(&p, ipe, ip, 1));
+ if (p - ip != bie - bp || memcmp(ip, bp, p - ip))
+ return gp_combine_cant_handle;
+ }
+ slen = 0;
+ }
+ if (slen) {
+ if (bp == buffer + rlen + infix_len)
+ infix_len += slen;
+ if (!append(&bp, bpe, &ip, slen))
+ return gp_combine_small_buffer;
+ }
+ if (ip == ipe) {
+ if (ipe == fname + flen) {
+ /* All done.
+ * Note that the case (prefix + plen == fname && flen == 0)
+ * falls here without appending a separator.
+ */
+ const char *zero="";
+
+ if (bp == buffer) {
+ /* Must not return empty path. */
+ const char *current = gp_file_name_current();
+ int clen = strlen(current);
+
+ if (!append(&bp, bpe, &current, clen))
+ return gp_combine_small_buffer;
+ }
+ *blen = bp - buffer;
+ if (!append(&bp, bpe, &zero, 1))
+ return gp_combine_small_buffer;
+ return gp_combine_success;
+ } else {
+ /* ipe == prefix + plen */
+ /* Switch to fname. */
+ ip = fname;
+ ipe = fname + flen;
+ if (slen == 0) {
+ /* Insert a separator. */
+ const char *sep;
+
+ slen = search_separator(&ip, ipe, fname, 1);
+ sep = (slen != 0 ? gp_file_name_directory_separator()
+ : gp_file_name_separator());
+ slen = strlen(sep);
+ if (bp == buffer + rlen + infix_len)
+ infix_len += slen;
+ if (!append(&bp, bpe, &sep, slen))
+ return gp_combine_small_buffer;
+ ip = fname; /* Switch to fname. */
+ }
+ }
+ }
+ }
+}
+
+/*
+ * Reduces parent references and current directory references when possible.
+ * The trailing zero byte is being added.
+ *
+ * Examples :
+ * "/gs/lib/../Resource/CMap/H" --> "/gs/Resource/CMap/H"
+ * "C:/gs/lib/../Resource/CMap/H" --> "C:/gs/Resource/CMap/H"
+ * "hard disk:gs:lib::Resource:CMap:H" -->
+ * "hard disk:gs:Resource:CMap:H"
+ * "DUA1:[GHOSTSCRIPT.LIB.-.RESOURCE.CMAP]H" -->
+ * "DUA1:[GHOSTSCRIPT.RESOURCE.CMAP]H"
+ * "\\server\share/a/b///c/../d.e/./../x.e/././/../../y.z/v.v" -->
+ * "\\server\share/a/y.z/v.v"
+ *
+ */
+gp_file_name_combine_result
+gp_file_name_reduce(const char *fname, uint flen, char *buffer, uint *blen)
+{
+ return gp_file_name_combine(fname, flen, fname + flen, 0, false, buffer, blen);
+}
+
+/*
+ * Answers whether a file name is absolute (starts from a root).
+ */
+bool
+gp_file_name_is_absolute(const char *fname, uint flen)
+{
+ return (gp_file_name_root(fname, flen) > 0);
+}
+
+/*
+ * Returns length of all starting parent references.
+ */
+static uint
+gp_file_name_prefix(const char *fname, uint flen,
+ bool (*test)(const char *fname, uint flen))
+{
+ uint plen = gp_file_name_root(fname, flen), slen;
+ const char *ip, *ipe;
+ const char *item = fname; /* plen == flen could cause an indeterminizm. */
+
+ if (plen > 0)
+ return 0;
+ ip = fname + plen;
+ ipe = fname + flen;
+ for (; ip < ipe; ) {
+ item = ip;
+ slen = search_separator(&ip, ipe, item, 1);
+ if (!(*test)(item, ip - item))
+ break;
+ ip += slen;
+ }
+ return item - fname;
+}
+
+/*
+ * Returns length of all starting parent references.
+ */
+uint
+gp_file_name_parents(const char *fname, uint flen)
+{
+ return gp_file_name_prefix(fname, flen, gp_file_name_is_parent);
+}
+
+/*
+ * Returns length of all starting cwd references.
+ */
+uint
+gp_file_name_cwds(const char *fname, uint flen)
+{
+ return gp_file_name_prefix(fname, flen, gp_file_name_is_current);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-05 23:05:09 +0000