xref: /freebsd/contrib/expat/xmlwf/readfilemap.c (revision fe9278888fd4414abe2d922e469cf608005f4c65)
1 /*
2                             __  __            _
3                          ___\ \/ /_ __   __ _| |_
4                         / _ \\  /| '_ \ / _` | __|
5                        |  __//  \| |_) | (_| | |_
6                         \___/_/\_\ .__/ \__,_|\__|
7                                  |_| XML parser
8 
9    Copyright (c) 1997-2000 Thai Open Source Software Center Ltd
10    Copyright (c) 2000      Clark Cooper <coopercc@users.sourceforge.net>
11    Copyright (c) 2001-2004 Fred L. Drake, Jr. <fdrake@users.sourceforge.net>
12    Copyright (c) 2002-2009 Karl Waclawek <karl@waclawek.net>
13    Copyright (c) 2016-2017 Sebastian Pipping <sebastian@pipping.org>
14    Copyright (c) 2017      Rhodri James <rhodri@wildebeest.org.uk>
15    Copyright (c) 2017      Franek Korta <fkorta@gmail.com>
16    Copyright (c) 2022      Sean McBride <sean@rogue-research.com>
17    Copyright (c) 2025      Hanno Böck <hanno@gentoo.org>
18    Licensed under the MIT license:
19 
20    Permission is  hereby granted,  free of charge,  to any  person obtaining
21    a  copy  of  this  software   and  associated  documentation  files  (the
22    "Software"),  to  deal in  the  Software  without restriction,  including
23    without  limitation the  rights  to use,  copy,  modify, merge,  publish,
24    distribute, sublicense, and/or sell copies of the Software, and to permit
25    persons  to whom  the Software  is  furnished to  do so,  subject to  the
26    following conditions:
27 
28    The above copyright  notice and this permission notice  shall be included
29    in all copies or substantial portions of the Software.
30 
31    THE  SOFTWARE  IS  PROVIDED  "AS  IS",  WITHOUT  WARRANTY  OF  ANY  KIND,
32    EXPRESS  OR IMPLIED,  INCLUDING  BUT  NOT LIMITED  TO  THE WARRANTIES  OF
33    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
34    NO EVENT SHALL THE AUTHORS OR  COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
35    DAMAGES OR  OTHER LIABILITY, WHETHER  IN AN  ACTION OF CONTRACT,  TORT OR
36    OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
37    USE OR OTHER DEALINGS IN THE SOFTWARE.
38 */
39 
40 #include <sys/types.h>
41 #include <sys/stat.h>
42 #include <fcntl.h>
43 #include <stdlib.h>
44 #include <stdio.h>
45 
46 /* Functions close(2) and read(2) */
47 #if ! defined(_WIN32) && ! defined(_WIN64)
48 #  include <unistd.h>
49 #endif
50 
51 /* Function "read": */
52 #if defined(_MSC_VER)
53 #  include <io.h>
54 /* https://msdn.microsoft.com/en-us/library/wyssk1bs(v=vs.100).aspx */
55 #  define EXPAT_read _read
56 #  define EXPAT_read_count_t int
57 #  define EXPAT_read_req_t unsigned int
58 #else /* POSIX */
59 /* https://pubs.opengroup.org/onlinepubs/009695399/functions/read.html */
60 #  define EXPAT_read read
61 #  define EXPAT_read_count_t ssize_t
62 #  define EXPAT_read_req_t size_t
63 #endif
64 
65 #ifndef S_ISREG
66 #  ifndef S_IFREG
67 #    define S_IFREG _S_IFREG
68 #  endif
69 #  ifndef S_IFMT
70 #    define S_IFMT _S_IFMT
71 #  endif
72 #  define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
73 #endif /* not S_ISREG */
74 
75 #ifndef O_BINARY
76 #  ifdef _O_BINARY
77 #    define O_BINARY _O_BINARY
78 #  else
79 #    define O_BINARY 0
80 #  endif
81 #endif
82 
83 #include "xmltchar.h"
84 #include "filemap.h"
85 
86 int
filemap(const tchar * name,void (* processor)(const void *,size_t,const tchar *,void * arg),void * arg)87 filemap(const tchar *name,
88         void (*processor)(const void *, size_t, const tchar *, void *arg),
89         void *arg) {
90   size_t nbytes;
91   int fd;
92   EXPAT_read_count_t n;
93   struct stat sb;
94   void *p;
95 
96   fd = topen(name, O_RDONLY | O_BINARY);
97   if (fd < 0) {
98     tperror(name);
99     return 0;
100   }
101   if (fstat(fd, &sb) < 0) {
102     tperror(name);
103     close(fd);
104     return 0;
105   }
106   if (! S_ISREG(sb.st_mode)) {
107     ftprintf(stderr, T("%s: not a regular file\n"), name);
108     close(fd);
109     return 0;
110   }
111   if (sb.st_size > XML_MAX_CHUNK_LEN) {
112     close(fd);
113     return 2; /* Cannot be passed to XML_Parse in one go */
114   }
115 
116   nbytes = sb.st_size;
117   /* malloc will return NULL with nbytes == 0, handle files with size 0 */
118   if (nbytes == 0) {
119     static const char c = '\0';
120     processor(&c, 0, name, arg);
121     close(fd);
122     return 1;
123   }
124   p = malloc(nbytes);
125   if (! p) {
126     ftprintf(stderr, T("%s: out of memory\n"), name);
127     close(fd);
128     return 0;
129   }
130   n = EXPAT_read(fd, p, (EXPAT_read_req_t)nbytes);
131   if (n < 0) {
132     tperror(name);
133     free(p);
134     close(fd);
135     return 0;
136   }
137   if (n != (EXPAT_read_count_t)nbytes) {
138     ftprintf(stderr, T("%s: read unexpected number of bytes\n"), name);
139     free(p);
140     close(fd);
141     return 0;
142   }
143   processor(p, nbytes, name, arg);
144   free(p);
145   close(fd);
146   return 1;
147 }
148