Minix代码讲解 PDF

MINIX SOURCE CODE File: include/ansi.h 1

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include/ansi.h

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00000 /* The <ansi.h> header attempts to decide whether the compiler has enough

00001 * conformance to Standard C for Minix to take advantage of. If so, the

00002 * symbol _ANSI is defined (as 31415). Otherwise _ANSI is not defined

00003 * here, but it may be defined by applications that want to bend the rules.

00004 * The magic number in the definition is to inhibit unnecessary bending

00011 * _PROTOTYPE(function, params)

00012 *

00013 * is defined. This macro expands in different ways, generating either

00014 * ANSI Standard C prototypes or old-style K&R (Kernighan & Ritchie)

00015 * prototypes, as needed. Finally, some programs use _CONST, _VOIDSTAR etc

00016 * in such a way that they are portable over both ANSI and K&R compilers.

00017 * The appropriate macros are defined here.

00018 */

00019

00020 #ifndef _ANSI_H

00027 #ifdef __GNUC__

00028 #define _ANSI 31459 /* gcc conforms enough even in non-ANSI mode */

00029 #endif

00030

00031 #ifdef _ANSI

00032

00033 /* Keep everything for ANSI prototypes. */

00034 #define _PROTOTYPE(function, params) function params

00035 #define _ARGS(params) params

00036

00043 #else

00044

00045 /* Throw away the parameters for K&R prototypes. */

00046 #define _PROTOTYPE(function, params) function()

00047 #define _ARGS(params) ()

00048

00049 #define _VOIDSTAR void *

00050 #define _VOID void

00051 #define _CONST

00052 #define _VOLATILE

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include/limits.h

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00100 /* The <limits.h> header defines some basic sizes, both of the language types

00101 * (e.g., the number of bits in an integer), and of the operating system (e.g.

00102 * the number of characters in a file name.

00103 */

00104

00105 #ifndef _LIMITS_H

00106 #define _LIMITS_H

00113 #define SCHAR_MAX 127 /* maximum value of a signed char */

00114 #define UCHAR_MAX 255 /* maximum value of an unsigned char */

00115 #define MB_LEN_MAX 1 /* maximum length of a multibyte char */

00116

00117 /* Definitions about shorts (16 bits in MINIX). */

00118 #define SHRT_MIN (-32767-1) /* minimum value of a short */

00119 #define SHRT_MAX 32767 /* maximum value of a short */

00120 #define USHRT_MAX 0xFFFF /* maximum value of unsigned short */

00121

00122 /* _EM_WSIZE is a compiler-generated symbol giving the word size in bytes. */

00129 #if _EM_WSIZE == 4

00130 #define INT_MIN (-2147483647-1) /* minimum value of a 32-bit int */

00131 #define INT_MAX 2147483647 /* maximum value of a 32-bit int */

00132 #define UINT_MAX 0xFFFFFFFF /* maximum value of an unsigned 32-bit int */

00133 #endif

00134

00135 /*Definitions about longs (32 bits in MINIX). */

00136 #define LONG_MIN (-2147483647L-1)/* minimum value of a long */

00137 #define LONG_MAX 2147483647L /* maximum value of a long */

00138 #define ULONG_MAX 0xFFFFFFFFL /* maximum value of an unsigned long */

00145 #define _POSIX_MAX_CANON 255 /* size of the canonical input queue */

00146 #define _POSIX_MAX_INPUT 255 /* you can type 255 chars ahead */

00147 #define _POSIX_NAME_MAX 14 /* a file name may have 14 chars */

00148 #define _POSIX_NGROUPS_MAX 0 /* supplementary group IDs are optional */

00149 #define _POSIX_OPEN_MAX 16 /* a process may have 16 files open */

00153 #define _POSIX_TZNAME_MAX 3 /* time zone names can be at least 3 chars */

00154 #define _POSIX_SSIZE_MAX 32767 /* read() must support 32767 byte reads */

00155

00156 /* Values actually implemented by MINIX (Tables 2-4, 2-5, 2-6, and 2-7). */

00157 /* Some of these old names had better be defined when not POSIX. */

00164 #define ARG_MAX 4096 /* args + environ on small machines */

00165 #endif

00166 #define CHILD_MAX _NO_LIMIT /* MINIX does not limit children */

00167 #define OPEN_MAX 20 /* # open files a process may have */

00168 #define LINK_MAX 127 /* # links a file may have */

00169 #define MAX_CANON 255 /* size of the canonical input queue */

00170 #define MAX_INPUT 255 /* size of the type-ahead buffer */

00171 #define NAME_MAX 14 /* # chars in a file name */

00172 #define PATH_MAX 255 /* # chars in a path name */

00173 #define PIPE_BUF 7168 /* # bytes in atomic write to a pipe */

00180 #endif /* _LIMITS_H */

00200 /* The <errno.h> header defines the numbers of the various errors that can

00201 * occur during program execution. They are visible to user programs and

00202 * should be small positive integers. However, they are also used within

00203 * MINIX, where they must be negative. For example, the READ system call is

00204 * executed internally by calling do_read(). This function returns either a

00205 * (negative) error number or a (positive) number of bytes actually read.

00206 *

00207 * To solve the problem of having the error numbers be negative inside the

00208 * the system and positive outside, the following mechanism is used. All the

00215 * will be defined, setting EPERM to (- 1), whereas when when this

00216 * file is included in an ordinary user program, EPERM has the value ( 1).

00217 */

00218

00219 #ifndef _ERRNO_H /* check if <errno.h> is already included */

00223 #ifdef _SYSTEM

00224 # define _SIGN -

00225 # define OK 0

00226 #else

00227 # define _SIGN

00234

00235 #define EGENERIC (_SIGN 99) /* generic error */

00236 #define EPERM (_SIGN 1) /* operation not permitted */

00237 #define ENOENT (_SIGN 2) /* no such file or directory */

00238 #define ESRCH (_SIGN 3) /* no such process */

00239 #define EINTR (_SIGN 4) /* interrupted function call */

00240 #define EIO (_SIGN 5) /* input/output error */

00241 #define ENXIO (_SIGN 6) /* no such device or address */

00242 #define E2BIG (_SIGN 7) /* arg list too long */

00243 #define ENOEXEC (_SIGN 8) /* exec format error */

00250 #define ENOTBLK (_SIGN 15) /* Extension: not a block special file */

00251 #define EBUSY (_SIGN 16) /* resource busy */

00252 #define EEXIST (_SIGN 17) /* file exists */

00253 #define EXDEV (_SIGN 18) /* improper link */

00254 #define ENODEV (_SIGN 19) /* no such device */

00255 #define ENOTDIR (_SIGN 20) /* not a directory */

00256 #define EISDIR (_SIGN 21) /* is a directory */

00257 #define EINVAL (_SIGN 22) /* invalid argument */

00258 #define ENFILE (_SIGN 23) /* too many open files in system */

00259 #define EMFILE (_SIGN 24) /* too many open files */

00283 #define EDSTNOTRCH (_SIGN 56) /* destination not reachable */

00284 #define EISCONN (_SIGN 57) /* all ready connected */

00285 #define EADDRINUSE (_SIGN 58) /* address in use */

00286 #define ECONNREFUSED (_SIGN 59) /* connection refused */

00287 #define ECONNRESET (_SIGN 60) /* connection reset */

00294

00295 /* The following are not POSIX errors, but they can still happen. */

00296 #define ELOCKED (_SIGN 101) /* can’t send message */

00297 #define EBADCALL (_SIGN 102) /* error on send/receive */

00298

00299 /* The following error codes are generated by the kernel itself. */

00300 #ifdef _SYSTEM

00301 #define E_BAD_DEST -1001 /* destination address illegal */

00302 #define E_BAD_SRC -1002 /* source address illegal */

00303 #define E_TRY_AGAIN -1003 /* can’t send-- tables full */

00310 #define E_BAD_ADDR -1010 /* bad address given to utility routine */

00311 #define E_BAD_PROC -1011 /* bad proc number given to utility */

00312 #endif /* _SYSTEM */

00313

00314 #endif /* _ERRNO_H */

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include/unistd.h

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00400 /* The <unistd.h> header contains a few miscellaneous manifest constants. */

00401

00402 #ifndef _UNISTD_H

00403 #define _UNISTD_H

00410

00411 #ifndef _SSIZE_T

00412 #define _SSIZE_T

00413 typedef int ssize_t;

00414 #endif