Mercurial > pub > dyncall > dyncall

comparison dyncallback/dyncall_alloc_wx_mmap.c @ 255:704c28fd9428

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
- added "Unknown" type as executable format #define next to PE, Mach and ELF ones for cases like Minix < 3.2.0 - allow builds on platforms missing mprotect() (e.g. Minix)
author Tassilo Philipp
date Wed, 17 May 2017 02:39:41 +0200
parents 047d2829bdf6
children f5577f6bf97a
comparison
equal deleted inserted replaced
254:9d70178c1ded 255:704c28fd9428
38 # else 38 # else
39 # error "Platform implementation missing for anonymous rwx memory" 39 # error "Platform implementation missing for anonymous rwx memory"
40 # endif 40 # endif
41 #endif 41 #endif
42 42
43 /* platforms without mprotect */
44 #if defined(DC__OS_Minix)
45 # define NO_MPROTECT
46 #endif
47
48 /* if no mprotect() available/wanted, make mmap alloc pages as rwx */
49 #if defined(NO_MPROTECT)
50 # define MMAP_PROT_INIT (PROT_READ|PROT_WRITE|PROT_EXEC)
51 #else
52 # define MMAP_PROT_INIT (PROT_READ|PROT_WRITE)
53 #endif
43 54
44 DCerror dcAllocWX(size_t size, void** pp) 55 DCerror dcAllocWX(size_t size, void** pp)
45 { 56 {
46 void* p; 57 void* p;
47 #if !defined(MAP_ANON) && defined(DC_UNIX) 58 #if !defined(MAP_ANON) && defined(DC_UNIX)
48 /* Hack around not having POSIX' MAP_ANON by going through /dev/zero; store 59 /* Hack around not having POSIX' MAP_ANON by going through /dev/zero; store
49 file descr to close on dcFreeWX at beginning of memory, as tiny hack */ 60 file descr to close on dcFreeWX at beginning of memory, as tiny hack */
50 int fd = open("/dev/zero", O_RDWR); 61 int fd = open("/dev/zero", O_RDWR);
51 if(fd == -1) 62 if(fd == -1)
52 return -1; 63 return -1;
53 p = mmap(0, size+sizeof(int), PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); 64 p = mmap(0, size+sizeof(int), MMAP_PROT_INIT, MAP_PRIVATE, fd, 0);
54 if(p == MAP_FAILED) { 65 if(p == MAP_FAILED) {
55 close(fd); 66 close(fd);
56 return -1; 67 return -1;
57 } 68 }
58 *(int*)p = fd; 69 *(int*)p = fd;
59 p += sizeof(int); 70 p += sizeof(int);
60 #else 71 #else
61 p = mmap(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); 72 p = mmap(0, size, MMAP_PROT_INIT, MAP_PRIVATE|MAP_ANON, -1, 0);
62 if(p == MAP_FAILED) 73 if(p == MAP_FAILED)
63 return -1; 74 return -1;
64 #endif 75 #endif
65 76
66 *pp = p; 77 *pp = p;
67 return 0; 78 return 0;
68 } 79 }
69 80
70 DCerror dcInitExecWX(void* p, size_t size) 81 DCerror dcInitExecWX(void* p, size_t size)
71 { 82 {
83 #if defined(NO_MPROTECT)
84 return 0;
85 #else
86
72 #if !defined(MAP_ANON) && defined(DC_UNIX) 87 #if !defined(MAP_ANON) && defined(DC_UNIX)
73 /* Fixup pointer for no-MAP_ANON workaround (see above) */ 88 /* Fixup pointer for no-MAP_ANON workaround (see above) */
74 p -= sizeof(int); 89 p -= sizeof(int);
75 size += sizeof(int); 90 size += sizeof(int);
76 #endif 91 #endif
77 return mprotect(p, size, PROT_READ|PROT_EXEC); 92 return mprotect(p, size, PROT_READ|PROT_EXEC);
93 #endif
78 } 94 }
79 95
80 void dcFreeWX(void* p, size_t size) 96 void dcFreeWX(void* p, size_t size)
81 { 97 {
82 #if !defined(MAP_ANON) && defined(DC_UNIX) 98 #if !defined(MAP_ANON) && defined(DC_UNIX)