求fat外部命令的源码以及一些写g4d外部命令需要了解的东西。。。

sunsea

如题，我想写一个ntfs的外部命令来，准备照葫芦画瓢，参考文献是那份nt4泄露的源码（我前几天在这发过）。。。谢谢

还有啥基础知识没，比如C标准库对应的g4d函数啥的以及调试方法等等。。。谢谢

sratlf

**** Running User Programs（外部命令，供开发人员参考） ****

从0.4.5起，用户可以自行编写程序以在GRUB4DOS中运行。
该可执行程序文件必须以8字节grub4dos EXEC签名结尾。
0x05, 0x18, 0x05, 0x03, 0xBA, 0xA7, 0xBA, 0xBC

程序的入口点在文件头，和DOS的.com文件很像（但我们是32位的程序)。
注：因为使用了linux gcc的特性，所以程序只能在linux下使用gcc进行编译。
附上一个简单的echo.c源码，供参考。

/*================ begin echo.c ================*/

/*
* 编译:
gcc -Wl,--build-id=none -m32 -mno-sse -nostdlib -fno-zero-initialized-in-bss -fno-function-cse -fno-jump-tables -Wl,-N -fPIE echo.c -o echo.o

* disassemble:              objdump -d echo.o
* confirm no relocation:    readelf -r echo.o
* generate executable:      objcopy -O binary echo.o echo
* 经过这一步之后生成的echo文件就是可以在grub4dos中运行的程序。
* and then the resultant echo will be grub4dos executable.
*/

/*
* This is a simple ECHO command, running under grub4dos.
*/
#define sprintf ((int (*)(char *, const char *, ...))((*(int **)0x8300)[0]))
#define printf(...) sprintf(NULL, __VA_ARGS__)
int i = 0x66666666; /* 这是必要的，看下面的注释。*/
/* gcc treat the following as data only if a global initialization like the
* above line occurs.
*/
/* GRUB4DOS可执行程序结尾必须有以下8个字节（EXEC签名） */
asm(".long 0x03051805");
asm(".long 0xBCBAA7BA");
/* 感谢上帝, gcc 会把上面的8个字按兵不动放在最终程序的最后面。
* 不要在这里插入其它任何代码.
*/
int main(char *arg,int flags)
{
return printf("%s\n",arg);
}
/*================ end echo.c ================*/

0x8300 是 grub4dos 系统函数(API)的入口点. 你可以在 asm.S 源码中找到它的定义.
目前可以使用的函数和变量:
http://grubutils.googlecode.com/svn/trunk/src/include/grub4dos.h

sunsea

sratlf 发表于 2014-12-3 20:40
**** Running User Programs（外部命令，供开发人员参考） ****
从0.4.5起，用户可以自行编写程序以在GRUB ...

首先，google挂了。。。
其次。main的第二个参数flag是什么鬼

sratlf

sunsea 发表于 2014-12-3 20:50
首先，google挂了。。。
其次。main的第二个参数flag是什么鬼

google的问题可以用vpn出去  天朝必备技能  至于main参数  我也不知道。。。这段是readme里的

chenall

不要使用C自带的函数.直接调用grub4dos提供的函数

flags可以不用管它,这个是用于判断当前命令运行的环境 ,比如是从菜单运行,还是从命令行运行的,或是通过批处理调用的.

1. /*
   
2. * The C code for a grub4dos executable may have defines as follows:
   
3. * 用于编写外部命令的函数定义。
   
4. */
   
5. #ifndef GRUB4DOS_2011_12_13
   
6. #define GRUB4DOS_2011_12_13
   
7. #undef NULL
   
8. #define NULL         ((void *) 0)
   
9. 
   
10. /* Error codes (descriptions are in common.c) */
    
11. typedef enum
    
12. {
    
13.   ERR_NONE = 0,
    
14.   ERR_BAD_FILENAME,
    
15.   ERR_BAD_FILETYPE,
    
16.   ERR_BAD_GZIP_DATA,
    
17.   ERR_BAD_GZIP_HEADER,
    
18.   ERR_BAD_PART_TABLE,
    
19.   ERR_BAD_VERSION,
    
20.   ERR_BELOW_1MB,
    
21.   ERR_BOOT_COMMAND,
    
22.   ERR_BOOT_FAILURE,
    
23.   ERR_BOOT_FEATURES,
    
24.   ERR_DEV_FORMAT,
    
25.   ERR_DEV_VALUES,
    
26.   ERR_EXEC_FORMAT,
    
27.   ERR_FILELENGTH,
    
28.   ERR_FILE_NOT_FOUND,
    
29.   ERR_FSYS_CORRUPT,
    
30.   ERR_FSYS_MOUNT,
    
31.   ERR_GEOM,
    
32.   ERR_NEED_LX_KERNEL,
    
33.   ERR_NEED_MB_KERNEL,
    
34.   ERR_NO_DISK,
    
35.   ERR_NO_PART,
    
36.   ERR_NUMBER_PARSING,
    
37.   ERR_OUTSIDE_PART,
    
38.   ERR_READ,
    
39.   ERR_SYMLINK_LOOP,
    
40.   ERR_UNRECOGNIZED,
    
41.   ERR_WONT_FIT,
    
42.   ERR_WRITE,
    
43.   ERR_BAD_ARGUMENT,
    
44.   ERR_UNALIGNED,
    
45.   ERR_PRIVILEGED,
    
46.   ERR_DEV_NEED_INIT,
    
47.   ERR_NO_DISK_SPACE,
    
48.   ERR_NUMBER_OVERFLOW,
    
49. 
    
50.   ERR_DEFAULT_FILE,
    
51.   ERR_DEL_MEM_DRIVE,
    
52.   ERR_DISABLE_A20,
    
53.   ERR_DOS_BACKUP,
    
54.   ERR_ENABLE_A20,
    
55.   ERR_EXTENDED_PARTITION,
    
56.   ERR_FILENAME_FORMAT,
    
57.   ERR_HD_VOL_START_0,
    
58.   ERR_INT13_ON_HOOK,
    
59.   ERR_INT13_OFF_HOOK,
    
60.   ERR_INVALID_BOOT_CS,
    
61.   ERR_INVALID_BOOT_IP,
    
62.   ERR_INVALID_FLOPPIES,
    
63.   ERR_INVALID_HARDDRIVES,
    
64.   ERR_INVALID_HEADS,
    
65.   ERR_INVALID_LOAD_LENGTH,
    
66.   ERR_INVALID_LOAD_OFFSET,
    
67.   ERR_INVALID_LOAD_SEGMENT,
    
68.   ERR_INVALID_SECTORS,
    
69.   ERR_INVALID_SKIP_LENGTH,
    
70.   ERR_INVALID_RAM_DRIVE,
    
71.   ERR_IN_SITU_FLOPPY,
    
72.   ERR_IN_SITU_MEM,
    
73.   ERR_MD_BASE,
    
74.   ERR_NON_CONTIGUOUS,
    
75.   ERR_NO_DRIVE_MAPPED,
    
76.   ERR_NO_HEADS,
    
77.   ERR_NO_SECTORS,
    
78.   ERR_PARTITION_TABLE_FULL,
    
79.   ERR_RD_BASE,
    
80.   ERR_SPECIFY_GEOM,
    
81.   ERR_SPECIFY_MEM,
    
82.   ERR_SPECIFY_RESTRICTION,
    
83. //  ERR_INVALID_RD_BASE,
    
84. //  ERR_INVALID_RD_SIZE,
    
85.   ERR_MD5_FORMAT,
    
86.   ERR_WRITE_GZIP_FILE,
    
87.   ERR_FUNC_CALL,
    
88. //  ERR_WRITE_TO_NON_MEM_DRIVE,
    
89.   ERR_INTERNAL_CHECK,
    
90.   ERR_KERNEL_WITH_PROGRAM,
    
91.   ERR_HALT,
    
92.   ERR_PARTITION_LOOP,
    
93.   ERR_NOT_ENOUGH_MEMORY,
    
94.   ERR_BAT_GOTO,
    
95.   ERR_BAT_CALL,
    
96. 
    
97.   MAX_ERR_NUM
    
98. } grub_error_t;
    
99. 
    
100. #define install_partition (*(unsigned long long *)0x8208)
     
101. #define boot_drive (*(unsigned long long *)0x8280)
     
102. #define pxe_yip (*(unsigned long *)0x8284)
     
103. #define pxe_sip (*(unsigned long *)0x8288)
     
104. #define pxe_gip (*(unsigned long *)0x828C)
     
105. #define filesize (*(unsigned long long *)0x8290)
     
106. #define saved_mem_upper (*(unsigned long *)0x8298)
     
107. #define saved_partition (*(unsigned long *)0x829C)
     
108. #define saved_drive (*(unsigned long *)0x82A0)
     
109. #define no_decompression (*(unsigned long *)0x82A4)
     
110. #define part_start (*(unsigned long long *)0x82A8)
     
111. #define part_length (*(unsigned long long *)0x82B0)
     
112. #define fb_status (*(unsigned long *)0x82B8)
     
113. #define is64bit (*(unsigned long *)0x82BC)
     
114. #define saved_mem_higher (*(unsigned long long *)0x82C0)
     
115. #define cdrom_drive (*(unsigned long *)0x82C8)
     
116. #define ram_drive (*(unsigned long *)0x82CC)
     
117. #define rd_base (*(unsigned long long *)0x82D0)
     
118. #define rd_size (*(unsigned long long *)0x82D8)
     
119. #define addr_system_functions (*(unsigned long *)0x8300)
     
120. #define next_partition_drive                ((*(unsigned long **)0x8304)[0])
     
121. #define next_partition_dest                ((*(unsigned long **)0x8304)[1])
     
122. #define next_partition_partition        ((*(unsigned long ***)0x8304)[2])
     
123. #define next_partition_type                ((*(unsigned long ***)0x8304)[3])
     
124. #define next_partition_start                ((*(unsigned long ***)0x8304)[4])
     
125. #define next_partition_len                ((*(unsigned long ***)0x8304)[5])
     
126. #define next_partition_offset                ((*(unsigned long ***)0x8304)[6])
     
127. #define next_partition_entry                ((*(unsigned long ***)0x8304)[7])
     
128. #define next_partition_ext_offset        ((*(unsigned long ***)0x8304)[8])
     
129. #define next_partition_buf                ((*(char ***)0x8304)[9])
     
130. #define quit_print                ((*(int **)0x8304)[10])
     
131. #define filesystem_type ((*(int **)0x8304)[13])
     
132. //#define query_block_entries ((*(long **)0x8304)[14])
     
133. //#define map_start_sector ((*(unsigned long **)0x8304)[15])
     
134. #define buf_geom ((*(struct geometry ***)0x8304)[16])
     
135. #define tmp_geom ((*(struct geometry ***)0x8304)[17])
     
136. #define term_table ((*(struct term_entry ***)0x8304)[18])
     
137. #define current_term ((*(struct term_entry ***)0x8304)[19])
     
138. #define fsys_table ((*(struct fsys_entry ***)0x8304)[20])
     
139. //#define fsys_type ((*(int **)0x8304)[21])
     
140. //#define NUM_FSYS ((*(const int **)0x8304)[22])
     
141. 
     
142. #define graphics_inited ((*(const int **)0x8304)[23])
     
143. #define VARIABLE_GRAPHICS ((char *)(*(int ***)0x8304)[24])
     
144. #define font8x16 ((*(char ***)0x8304)[25])
     
145. #define fontx ((*(int **)0x8304)[26])
     
146. #define fonty ((*(int **)0x8304)[27])
     
147. #define graphics_CURSOR ((*(int **)0x8304)[28])
     
148. #define menu_border ((*(struct border ***)0x8304)[29])
     
149. #define current_color ((*(int **)0x8304)[42])
     
150. #define foreground ((*(int **)0x8304)[43])
     
151. #define background ((*(int **)0x8304)[44])
     
152. #define p_get_cmdline_str ((*(int **)0x8304)[45])
     
153. #define splashimage_loaded ((*(unsigned long **)0x8304)[46])
     
154. #define putchar_hooked ((*(unsigned long **)0x8304)[47])
     
155. #define init_free_mem_start ((*(unsigned long **)0x8304)[48])
     
156. #define cursorX (*(short *)(VARIABLE_GRAPHICS))
     
157. #define cursorY (*(short *)(VARIABLE_GRAPHICS + 2))
     
158. #define cursorBuf ((char *)(VARIABLE_GRAPHICS + 6))
     
159. 
     
160. #define free_mem_start (*(unsigned long *)0x82F0)
     
161. #define free_mem_end (*(unsigned long *)0x82F4)
     
162. #define saved_mmap_addr (*(unsigned long *)0x82F8)
     
163. #define saved_mmap_length (*(unsigned long *)0x82FB)
     
164. 
     
165. #define DRIVE_MAP_SIZE        8
     
166. #define PXE_DRIVE                0x21
     
167. #define INITRD_DRIVE        0x22
     
168. #define FB_DRIVE                0x23
     
169. #define SECTOR_SIZE                0x200
     
170. #define SECTOR_BITS                9
     
171. #define BIOSDISK_FLAG_BIFURCATE                0x4
     
172. #define MB_ARD_MEMORY        1
     
173. #define MB_INFO_MEM_MAP        0x00000040
     
174. 
     
175. #define errnum (*(grub_error_t *)0x8314)
     
176. #define current_drive (*(unsigned long *)0x8318)
     
177. #define current_partition (*(unsigned long *)0x831C)
     
178. #define filemax (*(unsigned long long *)0x8320)
     
179. #define filepos (*(unsigned long long *)0x8328)
     
180. #define debug (*(int *)0x8330)
     
181. #define current_slice (*(unsigned long *)0x8334)
     
182. #define buf_track        (*(unsigned long long *)0x8340)
     
183. #define buf_drive        (*(int *)0x8348)
     
184. 
     
185. #define GRUB_READ 0xedde0d90
     
186. #define GRUB_WRITE 0x900ddeed
     
187. 
     
188. #define sprintf ((int (*)(char *, const char *, ...))((*(int **)0x8300)[0]))
     
189. #define printf(...) sprintf(NULL, __VA_ARGS__)
     
190. #define putstr ((void (*)(const char *))((*(int **)0x8300)[1]))
     
191. #define putchar ((void (*)(int))((*(int **)0x8300)[2]))
     
192. #define get_cmdline_obsolete ((int (*)(struct get_cmdline_arg cmdline))((*(int **)0x8300)[3]))
     
193. #define getxy ((int (*)(void))((*(int **)0x8300)[4]))
     
194. #define gotoxy ((void (*)(int, int))((*(int **)0x8300)[5]))
     
195. #define cls ((void (*)(void))((*(int **)0x8300)[6]))
     
196. #define wee_skip_to ((char *(*)(char *, int))((*(int **)0x8300)[7]))
     
197. #define nul_terminate ((int (*)(char *))((*(int **)0x8300)[8]))
     
198. #define safe_parse_maxint_with_suffix ((int (*)(char **str_ptr, unsigned long long *myint_ptr, int unitshift))((*(int **)0x8300)[9]))
     
199. #define safe_parse_maxint(str_ptr, myint_ptr) safe_parse_maxint_with_suffix(str_ptr, myint_ptr, 0)
     
200. #define substring ((int (*)(const char *s1, const char *s2, int case_insensitive))((*(int **)0x8300)[10]))
     
201. #define strstr ((char *(*)(const char *s1, const char *s2))((*(int **)0x8300)[11]))
     
202. #define strlen ((int (*)(const char *str))((*(int **)0x8300)[12]))
     
203. #define strtok ((char *(*)(char *s, const char *delim))((*(int **)0x8300)[13]))
     
204. #define strncat ((int (*)(char *s1, const char *s2, int n))((*(int **)0x8300)[14]))
     
205. //#define strcmp ((int (*)(const char *s1, const char *s2))((*(int **)0x8300)[15]))
     
206. #define strcpy ((char *(*)(char *dest, const char *src))((*(int **)0x8300)[16]))
     
207. #define getkey ((int (*)(void))((*(int **)0x8300)[19]))
     
208. #define checkkey ((int (*)(void))((*(int **)0x8300)[20]))
     
209. #define memcmp ((int (*)(const char *s1, const char *s2, int n))((*(int **)0x8300)[22]))
     
210. #define memmove ((void *(*)(void *to, const void *from, int len))((*(int **)0x8300)[23]))
     
211. #define memset ((void *(*)(void *start, int c, int len))((*(int **)0x8300)[24]))
     
212. #define open ((int (*)(char *))((*(int **)0x8300)[26]))
     
213. #define read ((unsigned long long (*)(unsigned long long, unsigned long long, unsigned long))((*(int **)0x8300)[27]))
     
214. #define close ((void (*)(void))((*(int **)0x8300)[28]))
     
215. #define devread ((int (*)(unsigned long long sector, unsigned long byte_offset, unsigned long long byte_len, unsigned long long buf, unsigned long write))((*(int **)0x8300)[32]))
     
216. /*
     
217. * int
     
218. * devwrite (unsigned long sector, unsigned long sector_count, char *buf)
     
219. */
     
220. #define devwrite ((int (*)(unsigned long, unsigned long, char *))((*(int **)0x8300)[33]))
     
221. #define next_partition ((int (*)(void))((*(int **)0x8300)[34]))
     
222. #define open_device ((int (*)(void))((*(int **)0x8300)[35]))
     
223. #define real_open_partition ((int (*)(int))((*(int **)0x8300)[36]))
     
224. #define set_device ((char *(*)(char *))((*(int **)0x8300)[37]))
     
225. #define parse_string ((int (*)(char *))((*(int **)0x8300)[41]))
     
226. #define hexdump ((void (*)(unsigned long long, char *, int))((*(int **)0x8300)[42]))
     
227. #define skip_to ((char *(*)(int after_equal, char *cmdline))((*(int **)0x8300)[43]))
     
228. #define builtin_cmd ((int (*)(char *cmd, char *arg, int flags))((*(int **)0x8300)[44]))
     
229. #define get_datetime ((void (*)(unsigned long *date, unsigned long *time))((*(int **)0x8300)[45]))
     
230. #define find_command ((struct builtin *(*)(char *))((*(int **)0x8300)[46]))
     
231. #define get_mmap_entry ((int (*)(char *,int))((*(int **)0x8300)[49]))
     
232. #define malloc ((void *(*)(int size))((*(int **)0x8300)[50]))
     
233. #define free ((void (*)(void *ptr))((*(int **)0x8300)[51]))
     
234. #define realmode_run ((int (*)(long regs_ptr))((*(int **)0x8300)[53]))
     
235. 
     
236. #define SKIP_LINE                0x100
     
237. #define SKIP_NONE                0
     
238. #define SKIP_WITH_TERMINATE        0x200
     
239. 
     
240. /*
     
241. int
     
242. devread (unsigned long drive, unsigned long sector, unsigned long byte_offset, unsigned long long byte_len, unsigned long long buf, unsigned long write)
     
243. */
     
244. #define grub_dir ((int (*)(char *))((*(int **)0x8300)[61]))
     
245. #define print_a_completion ((void (*)(char *, int))((*(int **)0x8300)[62]))
     
246. #define print_completions ((int (*)(int, int))((*(int **)0x8300)[63]))
     
247. #define lba_to_chs ((void (*)(unsigned long lba, unsigned long *cl, unsigned long *ch, unsigned long *dh))((*(int **)0x8300)[64]))
     
248. #define probe_bpb ((int (*)(struct master_and_dos_boot_sector *BS))((*(int **)0x8300)[65]))
     
249. #define probe_mbr ((int (*)(struct master_and_dos_boot_sector *BS, unsigned long start_sector1, unsigned long sector_count1, unsigned long part_start1))((*(int **)0x8300)[66]))
     
250. #define unicode_to_utf8 ((unsigned long (*)(unsigned short *, unsigned char *, unsigned long))((*(int **)0x8300)[67]))
     
251. /*
     
252. int
     
253. rawread (unsigned long drive, unsigned long long sector, unsigned long byte_offset, unsigned long byte_len, unsigned long long buf, unsigned long write)
     
254. */
     
255. #define rawread ((int (*)(unsigned long, unsigned long long, unsigned long, unsigned long long, unsigned long long, unsigned long))((*(int **)0x8300)[68]))
     
256. /*
     
257. int
     
258. rawwrite (unsigned long drive, unsigned long sector, char *buf)
     
259. */
     
260. #define rawwrite ((int (*)(unsigned long, unsigned long, char *))((*(int **)0x8300)[69]))
     
261. 
     
262. #define setcursor ((int (*)(int))((*(int **)0x8300)[70]))
     
263. #define tolower ((int (*)(int))((*(int **)0x8300)[71]))
     
264. #define isspace ((int (*)(int))((*(int **)0x8300)[72]))
     
265. #define sleep ((unsigned int (*)(unsigned int))((*(int **)0x8300)[73]))
     
266. #define mem64 ((int (*)(int, unsigned long long, unsigned long long, unsigned long long))((*(int **)0x8300)[74]))
     
267. //int envi_cmd(const char *var,char * const env,int flags);
     
268. #define envi_cmd ((int (*)(const char*, char *const, int))((*(int **)0x8300)[75]))
     
269. 
     
270. /* strncmpx 增强型字符串比较函数 by chenall 2011-12-13
     
271.         int strncmpx(const char *s1,const char *s2, unsigned long n, int case_insensitive)
     
272.         比较两个字符串s1,s2.长度: n,
     
273.         如果n等于0，则只比较到字符串结束位置。否则比较指定长度n.不管字符串是否结束。
     
274.         如果case_insensitive非0，比较字母时不区分大小写。
     
275.         可以替换strcmp/memcmp等字符串比较函数
     
276.         返回值: s1-s2
     
277.                 当s1<s2时，返回值<0
     
278.                 当s1=s2时，返回值=0
     
279.                 当s1>s2时，返回值>0
     
280. */
     
281. #define strncmpx ((int (*)(const char*, const char*, unsigned long,int))((*(int **)0x8300)[76]))
     
282. /*
     
283.         以下几个字符串比较都是使用strncmpx来实现
     
284. */
     
285. //比较字符串s1和s2。
     
286. #define strcmp(s1,s2) strncmpx(s1,s2,0,0)
     
287. //比较字符串s1和s2。不区分大小写
     
288. #define stricmp(s1,s2) strncmpx(s1,s2,0,1)
     
289. #define strcmpi stricmp
     
290. //比较字符串s1和s2的前n个字符。
     
291. #define strncmp(s1,s2,n) strncmpx(s1,s2,n,0)
     
292. //比较字符串s1和s2的前n个字符但不区分大小写。
     
293. #define strnicmp(s1,s2,n) strncmpx(s1,s2,n,1)
     
294. #define strncmpi strnicmp
     
295. 
     
296. //void rectangle(int left, int top, int length, int width, int line);
     
297. #define rectangle ((void (*)(int,int,int,int,int))((*(int **)0x8300)[77]))
     
298. 
     
299. #define get_cmdline ((int (*)(void))((*(int **)0x8300)[78]))
     
300. 
     
301. #define RAW_ADDR(x) (x)
     
302. #define SCRATCHADDR  RAW_ADDR (0x37e00)
     
303. #define MBR ((char *)0x8000)
     
304. //#define grub_memcmp memcmp
     
305. struct get_cmdline_arg
     
306. {
     
307.         char *cmdline;
     
308.         char *prompt;
     
309.         int maxlen;
     
310.         int echo_char;
     
311.         int readline;
     
312. } __attribute__ ((packed));
     
313. 
     
314. struct geometry
     
315. {
     
316.   /* The number of cylinders */
     
317.   unsigned long cylinders;
     
318.   /* The number of heads */
     
319.   unsigned long heads;
     
320.   /* The number of sectors */
     
321.   unsigned long sectors;
     
322.   /* The total number of sectors */
     
323.   unsigned long long total_sectors;
     
324.   /* Device sector size */
     
325.   unsigned long sector_size;
     
326.   /* Flags */
     
327.   unsigned long flags;
     
328. };
     
329. 
     
330. /* fsys.h */
     
331. struct fsys_entry
     
332. {
     
333.   char *name;
     
334.   int (*mount_func) (void);
     
335.   unsigned long (*read_func) (unsigned long long buf, unsigned long long len, unsigned long write);
     
336.   int (*dir_func) (char *dirname);
     
337.   void (*close_func) (void);
     
338.   unsigned long (*embed_func) (unsigned long *start_sector, unsigned long needed_sectors);
     
339. };
     
340. /* fsys.h */
     
341. 
     
342. /* shared.h */
     
343. struct master_and_dos_boot_sector {
     
344. /* 00 */ char dummy1[0x0b]; /* at offset 0, normally there is a short JMP instuction(opcode is 0xEB) */
     
345. /* 0B */ unsigned short bytes_per_sector __attribute__ ((packed));/* seems always to be 512, so we just use 512 */
     
346. /* 0D */ unsigned char sectors_per_cluster;/* non-zero, the power of 2, i.e., 2^n */
     
347. /* 0E */ unsigned short reserved_sectors __attribute__ ((packed));/* FAT=non-zero, NTFS=0? */
     
348. /* 10 */ unsigned char number_of_fats;/* NTFS=0; FAT=1 or 2  */
     
349. /* 11 */ unsigned short root_dir_entries __attribute__ ((packed));/* FAT32=0, NTFS=0, FAT12/16=non-zero */
     
350. /* 13 */ unsigned short total_sectors_short __attribute__ ((packed));/* FAT32=0, NTFS=0, FAT12/16=any */
     
351. /* 15 */ unsigned char media_descriptor;/* range from 0xf0 to 0xff */
     
352. /* 16 */ unsigned short sectors_per_fat __attribute__ ((packed));/* FAT32=0, NTFS=0, FAT12/16=non-zero */
     
353. /* 18 */ unsigned short sectors_per_track __attribute__ ((packed));/* range from 1 to 63 */
     
354. /* 1A */ unsigned short total_heads __attribute__ ((packed));/* range from 1 to 256 */
     
355. /* 1C */ unsigned long hidden_sectors __attribute__ ((packed));/* any value */
     
356. /* 20 */ unsigned long total_sectors_long __attribute__ ((packed));/* FAT32=non-zero, NTFS=0, FAT12/16=any */
     
357. /* 24 */ unsigned long sectors_per_fat32 __attribute__ ((packed));/* FAT32=non-zero, NTFS=any, FAT12/16=any */
     
358. /* 28 */ unsigned long long total_sectors_long_long __attribute__ ((packed));/* NTFS=non-zero, FAT12/16/32=any */
     
359. /* 30 */ char dummy2[0x18e];
     
360. 
     
361.     /* Partition Table, starting at offset 0x1BE */
     
362. /* 1BE */ struct {
     
363.         /* +00 */ unsigned char boot_indicator;
     
364.         /* +01 */ unsigned char start_head;
     
365.         /* +02 */ unsigned short start_sector_cylinder __attribute__ ((packed));
     
366.         /* +04 */ unsigned char system_indicator;
     
367.         /* +05 */ unsigned char end_head;
     
368.         /* +06 */ unsigned short end_sector_cylinder __attribute__ ((packed));
     
369.         /* +08 */ unsigned long start_lba __attribute__ ((packed));
     
370.         /* +0C */ unsigned long total_sectors __attribute__ ((packed));
     
371.         /* +10 */
     
372.     } P[4];
     
373. /* 1FE */ unsigned short boot_signature __attribute__ ((packed));/* 0xAA55 */
     
374. #if 0
     
375.          /* This starts at offset 0x200 */
     
376. /* 200 */ unsigned long probed_total_sectors __attribute__ ((packed));
     
377. /* 204 */ unsigned long probed_heads __attribute__ ((packed));
     
378. /* 208 */ unsigned long probed_sectors_per_track __attribute__ ((packed));
     
379. /* 20C */ unsigned long probed_cylinders __attribute__ ((packed));
     
380. /* 210 */ unsigned long sectors_per_cylinder __attribute__ ((packed));
     
381. /* 214 */ char dummy3[0x0c] __attribute__ ((packed));
     
382. 
     
383.     /* matrix of coefficients of linear equations
     
384.      *
     
385.      *   C[n] * (H_count * S_count) + H[n] * S_count = LBA[n] - S[n] + 1
     
386.      *
     
387.      * where n = 1, 2, 3, 4, 5, 6, 7, 8
     
388.      */
     
389.          /* This starts at offset 0x130 */
     
390. /* 220 */ long long L[9] __attribute__ ((packed)); /* L[n] == LBA[n] - S[n] + 1 */
     
391. /* 268 */ long H[9] __attribute__ ((packed));
     
392. /* 28C */ short C[9] __attribute__ ((packed));
     
393. /* 29E */ short X __attribute__ ((packed));
     
394. /* 2A0 */ short Y __attribute__ ((packed));
     
395. /* 2A2 */ short Cmax __attribute__ ((packed));
     
396. /* 2A4 */ long Hmax __attribute__ ((packed));
     
397. /* 2A8 */ unsigned long Z __attribute__ ((packed));
     
398. /* 2AC */ short Smax __attribute__ ((packed));
     
399. /* 2AE */
     
400. #endif
     
401.   };
     
402. 
     
403. struct drive_map_slot
     
404. {
     
405.         /* Remember to update DRIVE_MAP_SLOT_SIZE once this is modified.
     
406.          * The struct size must be a multiple of 4.
     
407.          */
     
408. 
     
409.           /* X=max_sector bit 7: read only or fake write */
     
410.           /* Y=to_sector  bit 6: safe boot or fake write */
     
411.           /* ------------------------------------------- */
     
412.           /* X Y: meaning of restrictions imposed on map */
     
413.           /* ------------------------------------------- */
     
414.           /* 1 1: read only=0, fake write=1, safe boot=0 */
     
415.           /* 1 0: read only=1, fake write=0, safe boot=0 */
     
416.           /* 0 1: read only=0, fake write=0, safe boot=1 */
     
417.           /* 0 0: read only=0, fake write=0, safe boot=0 */
     
418. 
     
419.         unsigned char from_drive;
     
420.         unsigned char to_drive;                /* 0xFF indicates a memdrive */
     
421.         unsigned char max_head;
     
422.         unsigned char max_sector;        /* bit 7: read only */
     
423.                                         /* bit 6: disable lba */
     
424. 
     
425.         unsigned short to_cylinder;        /* max cylinder of the TO drive */
     
426.                                         /* bit 15:  TO  drive support LBA */
     
427.                                         /* bit 14:  TO  drive is CDROM(with big 2048-byte sector) */
     
428.                                         /* bit 13: FROM drive is CDROM(with big 2048-byte sector) */
     
429. 
     
430.         unsigned char to_head;                /* max head of the TO drive */
     
431.         unsigned char to_sector;        /* max sector of the TO drive */
     
432.                                         /* bit 7: in-situ */
     
433.                                         /* bit 6: fake-write or safe-boot */
     
434. 
     
435.         unsigned long long start_sector;
     
436.         //unsigned long start_sector_hi;        /* hi dword of the 64-bit value */
     
437.         unsigned long long sector_count;
     
438.         //unsigned long sector_count_hi;        /* hi dword of the 64-bit value */
     
439. };
     
440. 
     
441. 
     
442. /* shared.h */
     
443. 
     
444. typedef enum
     
445. {
     
446.         COLOR_STATE_STANDARD,
     
447.         /* represents the user defined colors for normal text */
     
448.         COLOR_STATE_NORMAL,
     
449.         /* represents the user defined colors for highlighted text */
     
450.         COLOR_STATE_HIGHLIGHT,
     
451.         /* represents the user defined colors for help text */
     
452.         COLOR_STATE_HELPTEXT,
     
453.         /* represents the user defined colors for heading line */
     
454.         COLOR_STATE_HEADING
     
455. } color_state;
     
456. 
     
457. struct term_entry
     
458. {
     
459.   /* The name of a terminal.  */
     
460.   const char *name;
     
461.   /* The feature flags defined above.  */
     
462.   unsigned long flags;
     
463.   unsigned short chars_per_line;
     
464.   /* Default for maximum number of lines if not specified */
     
465.   unsigned short max_lines;
     
466.   /* Put a character.  */
     
467.   void (*PUTCHAR) (int c);
     
468.   /* Check if any input character is available.  */
     
469.   int (*CHECKKEY) (void);
     
470.   /* Get a character.  */
     
471.   int (*GETKEY) (void);
     
472.   /* Get the cursor position. The return value is ((X << 8) | Y).  */
     
473.   int (*GETXY) (void);
     
474.   /* Go to the position (X, Y).  */
     
475.   void (*GOTOXY) (int x, int y);
     
476.   /* Clear the screen.  */
     
477.   void (*CLS) (void);
     
478.   /* Set the current color to be used */
     
479.   void (*SETCOLORSTATE) (color_state state);
     
480.   /* Set the normal color and the highlight color. The format of each
     
481.      color is VGA's.  */
     
482.   void (*SETCOLOR) (unsigned long state,unsigned long long color[]);
     
483.   /* Turn on/off the cursor.  */
     
484.   int (*SETCURSOR) (int on);
     
485. 
     
486.   /* function to start a terminal */
     
487.   int (*STARTUP) (void);
     
488.   /* function to use to shutdown a terminal */
     
489.   void (*SHUTDOWN) (void);
     
490. };
     
491. 
     
492. /* The table for a builtin.  */
     
493. struct builtin
     
494. {
     
495.   /* The command name.  */
     
496.   char *name;
     
497.   /* The callback function.  */
     
498.   int (*func) (char *, int);
     
499.   /* The combination of the flags defined above.  */
     
500.   int flags;
     
501.   /* The short version of the documentation.  */
     
502.   char *short_doc;
     
503.   /* The long version of the documentation.  */
     
504.   char *long_doc;
     
505. };
     
506. 
     
507. #endif

复制代码

sunsea

chenall 发表于 2014-12-4 08:35
不要使用C自带的函数.直接调用grub4dos提供的函数

flags可以不用管它,这个是用于判断当前命令运行的环境 ...

谢了，看来我得先实现一套C标准库的功能了

sunsea

chenall 发表于 2014-12-4 08:35
不要使用C自带的函数.直接调用grub4dos提供的函数

flags可以不用管它,这个是用于判断当前命令运行的环境 ...

谢谢，还有fat外部命令的源码哪边能搞到

chenall

要学会翻Q,很多好的东西都在外面的世界呢,,