github.com/afumu/libc@v0.0.6/musl/src/misc/ioctl.c (about) 1 #include <sys/ioctl.h> 2 #include <stdarg.h> 3 #include <errno.h> 4 #include <time.h> 5 #include <sys/time.h> 6 #include <stddef.h> 7 #include <string.h> 8 #include "syscall.h" 9 10 #define alignof(t) offsetof(struct { char c; t x; }, x) 11 12 #define W 1 13 #define R 2 14 #define WR 3 15 16 struct ioctl_compat_map { 17 int new_req, old_req; 18 unsigned char old_size, dir, force_align, noffs; 19 unsigned char offsets[8]; 20 }; 21 22 #define NINTH(a,b,c,d,e,f,g,h,i,...) i 23 #define COUNT(...) NINTH(__VA_ARGS__,8,7,6,5,4,3,2,1,0) 24 #define OFFS(...) COUNT(__VA_ARGS__), { __VA_ARGS__ } 25 26 /* yields a type for a struct with original size n, with a misaligned 27 * timeval/timespec expanded from 32- to 64-bit. for use with ioctl 28 * number producing macros; only size of result is meaningful. */ 29 #define new_misaligned(n) struct { int i; time_t t; char c[(n)-4]; } 30 31 static const struct ioctl_compat_map compat_map[] = { 32 { SIOCGSTAMP, SIOCGSTAMP_OLD, 8, R, 0, OFFS(0, 4) }, 33 { SIOCGSTAMPNS, SIOCGSTAMPNS_OLD, 8, R, 0, OFFS(0, 4) }, 34 35 /* SNDRV_TIMER_IOCTL_STATUS */ 36 { _IOR('T', 0x14, char[96]), _IOR('T', 0x14, 88), 88, R, 0, OFFS(0,4) }, 37 38 /* SNDRV_PCM_IOCTL_STATUS[_EXT] */ 39 { _IOR('A', 0x20, char[128]), _IOR('A', 0x20, char[108]), 108, R, 1, OFFS(4,8,12,16,52,56,60,64) }, 40 { _IOWR('A', 0x24, char[128]), _IOWR('A', 0x24, char[108]), 108, WR, 1, OFFS(4,8,12,16,52,56,60,64) }, 41 42 /* SNDRV_RAWMIDI_IOCTL_STATUS */ 43 { _IOWR('W', 0x20, char[48]), _IOWR('W', 0x20, char[36]), 36, WR, 1, OFFS(4,8) }, 44 45 /* SNDRV_PCM_IOCTL_SYNC_PTR - with 3 subtables */ 46 { _IOWR('A', 0x23, char[136]), _IOWR('A', 0x23, char[132]), 0, WR, 1, 0 }, 47 { 0, 0, 4, WR, 1, 0 }, /* snd_pcm_sync_ptr (flags only) */ 48 { 0, 0, 32, WR, 1, OFFS(8,12,16,24,28) }, /* snd_pcm_mmap_status */ 49 { 0, 0, 8, WR, 1, OFFS(0,4) }, /* snd_pcm_mmap_control */ 50 51 /* VIDIOC_QUERYBUF, VIDIOC_QBUF, VIDIOC_DQBUF, VIDIOC_PREPARE_BUF */ 52 { _IOWR('V', 9, new_misaligned(72)), _IOWR('V', 9, char[72]), 72, WR, 0, OFFS(20) }, 53 { _IOWR('V', 15, new_misaligned(72)), _IOWR('V', 15, char[72]), 72, WR, 0, OFFS(20) }, 54 { _IOWR('V', 17, new_misaligned(72)), _IOWR('V', 17, char[72]), 72, WR, 0, OFFS(20) }, 55 { _IOWR('V', 93, new_misaligned(72)), _IOWR('V', 93, char[72]), 72, WR, 0, OFFS(20) }, 56 57 /* VIDIOC_DQEVENT */ 58 { _IOR('V', 89, new_misaligned(96)), _IOR('V', 89, char[96]), 96, R, 0, OFFS(76,80) }, 59 60 /* VIDIOC_OMAP3ISP_STAT_REQ */ 61 { _IOWR('V', 192+6, char[32]), _IOWR('V', 192+6, char[24]), 22, WR, 0, OFFS(0,4) }, 62 63 /* PPPIOCGIDLE */ 64 { _IOR('t', 63, char[16]), _IOR('t', 63, char[8]), 8, R, 0, OFFS(0,4) }, 65 66 /* PPGETTIME, PPSETTIME */ 67 { _IOR('p', 0x95, char[16]), _IOR('p', 0x95, char[8]), 8, R, 0, OFFS(0,4) }, 68 { _IOW('p', 0x96, char[16]), _IOW('p', 0x96, char[8]), 8, W, 0, OFFS(0,4) }, 69 70 /* LPSETTIMEOUT */ 71 { _IOW(0x6, 0xf, char[16]), 0x060f, 8, W, 0, OFFS(0,4) }, 72 }; 73 74 static void convert_ioctl_struct(const struct ioctl_compat_map *map, char *old, char *new, int dir) 75 { 76 int new_offset = 0; 77 int old_offset = 0; 78 int old_size = map->old_size; 79 if (!(dir & map->dir)) return; 80 if (!map->old_size) { 81 /* offsets hard-coded for SNDRV_PCM_IOCTL_SYNC_PTR; 82 * if another exception appears this needs changing. */ 83 convert_ioctl_struct(map+1, old, new, dir); 84 convert_ioctl_struct(map+2, old+4, new+8, dir); 85 convert_ioctl_struct(map+3, old+68, new+72, dir); 86 return; 87 } 88 for (int i=0; i < map->noffs; i++) { 89 int ts_offset = map->offsets[i]; 90 int len = ts_offset-old_offset; 91 if (dir==W) memcpy(old+old_offset, new+new_offset, len); 92 else memcpy(new+new_offset, old+old_offset, len); 93 new_offset += len; 94 old_offset += len; 95 long long new_ts; 96 long old_ts; 97 int align = map->force_align ? sizeof(time_t) : alignof(time_t); 98 new_offset += (align-1) & -new_offset; 99 if (dir==W) { 100 memcpy(&new_ts, new+new_offset, sizeof new_ts); 101 old_ts = new_ts; 102 memcpy(old+old_offset, &old_ts, sizeof old_ts); 103 } else { 104 memcpy(&old_ts, old+old_offset, sizeof old_ts); 105 new_ts = old_ts; 106 memcpy(new+new_offset, &new_ts, sizeof new_ts); 107 } 108 new_offset += sizeof new_ts; 109 old_offset += sizeof old_ts; 110 } 111 if (dir==W) memcpy(old+old_offset, new+new_offset, old_size-old_offset); 112 else memcpy(new+new_offset, old+old_offset, old_size-old_offset); 113 } 114 115 int ioctl(int fd, int req, ...) 116 { 117 void *arg; 118 va_list ap; 119 va_start(ap, req); 120 arg = va_arg(ap, void *); 121 va_end(ap); 122 int r = __syscall(SYS_ioctl, fd, req, arg); 123 if (SIOCGSTAMP != SIOCGSTAMP_OLD && req && r==-ENOTTY) { 124 for (int i=0; i<sizeof compat_map/sizeof *compat_map; i++) { 125 if (compat_map[i].new_req != req) continue; 126 union { 127 long long align; 128 char buf[256]; 129 } u; 130 convert_ioctl_struct(&compat_map[i], u.buf, arg, W); 131 r = __syscall(SYS_ioctl, fd, compat_map[i].old_req, u.buf); 132 if (r<0) break; 133 convert_ioctl_struct(&compat_map[i], u.buf, arg, R); 134 break; 135 } 136 } 137 return __syscall_ret(r); 138 }