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Diffstat (limited to 'gdb/RCS/remote.c,v')
-rw-r--r-- | gdb/RCS/remote.c,v | 662 |
1 files changed, 662 insertions, 0 deletions
diff --git a/gdb/RCS/remote.c,v b/gdb/RCS/remote.c,v new file mode 100644 index 0000000..213113d --- /dev/null +++ b/gdb/RCS/remote.c,v @@ -0,0 +1,662 @@ +head 1.2; +access ; +symbols ; +locks ; strict; +comment @ * @; + + +1.2 +date 89.03.27.20.21.22; author gnu; state Exp; +branches ; +next 1.1; + +1.1 +date 89.03.20.18.45.46; author gnu; state Exp; +branches ; +next ; + + +desc +@@ + + +1.2 +log +@Avoid <sys/fcntl.h>. +@ +text +@/* Memory-access and commands for inferior process, for GDB. + Copyright (C) 1988 Free Software Foundation, Inc. + +GDB is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY. No author or distributor accepts responsibility to anyone +for the consequences of using it or for whether it serves any +particular purpose or works at all, unless he says so in writing. +Refer to the GDB General Public License for full details. + +Everyone is granted permission to copy, modify and redistribute GDB, +but only under the conditions described in the GDB General Public +License. A copy of this license is supposed to have been given to you +along with GDB so you can know your rights and responsibilities. It +should be in a file named COPYING. Among other things, the copyright +notice and this notice must be preserved on all copies. + +In other words, go ahead and share GDB, but don't try to stop +anyone else from sharing it farther. Help stamp out software hoarding! +*/ + +/* Remote communication protocol. + All values are encoded in ascii hex digits. + + Request Packet + + read registers g + reply XX....X Each byte of register data + is described by two hex digits. + Registers are in the internal order + for GDB, and the bytes in a register + are in the same order the machine uses. + or ENN for an error. + + write regs GXX..XX Each byte of register data + is described by two hex digits. + reply OK for success + ENN for an error + + read mem mAA..AA,LLLL AA..AA is address, LLLL is length. + reply XX..XX XX..XX is mem contents + or ENN NN is errno + + write mem MAA..AA,LLLL:XX..XX + AA..AA is address, + LLLL is number of bytes, + XX..XX is data + reply OK for success + ENN for an error + + cont cAA..AA AA..AA is address to resume + If AA..AA is omitted, + resume at same address. + + step sAA..AA AA..AA is address to resume + If AA..AA is omitted, + resume at same address. + + There is no immediate reply to step or cont. + The reply comes when the machine stops. + It is SAA AA is the "signal number" + + kill req k +*/ + +#include "defs.h" +#include "param.h" +#include "frame.h" +#include "inferior.h" + +#include "wait.h" + +#ifdef USG +#include <sys/types.h> +#include <fcntl.h> +#endif + +#include <stdio.h> +#include <signal.h> +#include <sys/ioctl.h> +#include <sys/file.h> + +#ifdef HAVE_TERMIO +#include <termio.h> +#undef TIOCGETP +#define TIOCGETP TCGETA +#undef TIOCSETN +#define TIOCSETN TCSETA +#undef TIOCSETP +#define TIOCSETP TCSETAF +#define TERMINAL struct termio +#else +#include <sgtty.h> +#define TERMINAL struct sgttyb +#endif + +int kiodebug; + +int icache; + +/* Descriptor for I/O to remote machine. */ +int remote_desc; + +#define PBUFSIZ 400 + +static void remote_send (); +static void putpkt (); +static void getpkt (); +static void dcache_flush (); + + +/* Open a connection to a remote debugger. + NAME is the filename used for communication. */ + +void +remote_open (name, from_tty) + char *name; + int from_tty; +{ + TERMINAL sg; + + remote_debugging = 0; + dcache_init (); + + remote_desc = open (name, O_RDWR); + if (remote_desc < 0) + perror_with_name (name); + + ioctl (remote_desc, TIOCGETP, &sg); +#ifdef HAVE_TERMIO + sg.c_lflag &= ~ICANON; +#else + sg.sg_flags = RAW; +#endif + ioctl (remote_desc, TIOCSETP, &sg); + + if (from_tty) + printf ("Remote debugging using %s\n", name); + remote_debugging = 1; +} + +/* Convert hex digit A to a number. */ + +static int +fromhex (a) + int a; +{ + if (a >= '0' && a <= '9') + return a - '0'; + else if (a >= 'a' && a <= 'f') + return a - 'a' + 10; + else + error ("Reply contains invalid hex digit"); +} + +/* Convert number NIB to a hex digit. */ + +static int +tohex (nib) + int nib; +{ + if (nib < 10) + return '0'+nib; + else + return 'a'+nib-10; +} + +/* Tell the remote machine to resume. */ + +int +remote_resume (step, signal) + int step, signal; +{ + char buf[PBUFSIZ]; + + dcache_flush (); + + strcpy (buf, step ? "s": "c"); + + putpkt (buf); +} + +/* Wait until the remote machine stops, then return, + storing status in STATUS just as `wait' would. */ + +int +remote_wait (status) + WAITTYPE *status; +{ + char buf[PBUFSIZ]; + + WSETEXIT ((*status), 0); + getpkt (buf); + if (buf[0] == 'E') + error ("Remote failure reply: %s", buf); + if (buf[0] != 'S') + error ("Invalid remote reply: %s", buf); + WSETSTOP ((*status), (((fromhex (buf[1])) << 4) + (fromhex (buf[2])))); +} + +/* Read the remote registers into the block REGS. */ + +void +remote_fetch_registers (regs) + char *regs; +{ + char buf[PBUFSIZ]; + int i; + char *p; + + sprintf (buf, "g"); + remote_send (buf); + + /* Reply describes registers byte by byte, + each byte encoded as two hex characters. */ + + p = buf; + for (i = 0; i < REGISTER_BYTES; i++) + { + if (p[0] == 0 || p[1] == 0) + error ("Remote reply is too short: %s", buf); + regs[i] = fromhex (p[0]) * 16 + fromhex (p[1]); + p += 2; + } +} + +/* Store the remote registers from the contents of the block REGS. */ + +void +remote_store_registers (regs) + char *regs; +{ + char buf[PBUFSIZ]; + int i; + char *p; + + buf[0] = 'G'; + + /* Command describes registers byte by byte, + each byte encoded as two hex characters. */ + + p = buf + 1; + for (i = 0; i < REGISTER_BYTES; i++) + { + *p++ = tohex ((regs[i] >> 4) & 0xf); + *p++ = tohex (regs[i] & 0xf); + } + + remote_send (buf); +} + +/* Read a word from remote address ADDR and return it. + This goes through the data cache. */ + +int +remote_fetch_word (addr) + CORE_ADDR addr; +{ + if (icache) + { + extern CORE_ADDR text_start, text_end; + + if (addr >= text_start && addr < text_end) + { + int buffer; + xfer_core_file (addr, &buffer, sizeof (int)); + return buffer; + } + } + return dcache_fetch (addr); +} + +/* Write a word WORD into remote address ADDR. + This goes through the data cache. */ + +void +remote_store_word (addr, word) + CORE_ADDR addr; + int word; +{ + dcache_poke (addr, word); +} + +/* Write memory data directly to the remote machine. + This does not inform the data cache; the data cache uses this. + MEMADDR is the address in the remote memory space. + MYADDR is the address of the buffer in our space. + LEN is the number of bytes. */ + +void +remote_write_bytes (memaddr, myaddr, len) + CORE_ADDR memaddr; + char *myaddr; + int len; +{ + char buf[PBUFSIZ]; + int i; + char *p; + + if (len > PBUFSIZ / 2 - 20) + abort (); + + sprintf (buf, "M%x,%x:", memaddr, len); + + /* Command describes registers byte by byte, + each byte encoded as two hex characters. */ + + p = buf + strlen (buf); + for (i = 0; i < len; i++) + { + *p++ = tohex ((myaddr[i] >> 4) & 0xf); + *p++ = tohex (myaddr[i] & 0xf); + } + + remote_send (buf); +} + +/* Read memory data directly from the remote machine. + This does not use the data cache; the data cache uses this. + MEMADDR is the address in the remote memory space. + MYADDR is the address of the buffer in our space. + LEN is the number of bytes. */ + +void +remote_read_bytes (memaddr, myaddr, len) + CORE_ADDR memaddr; + char *myaddr; + int len; +{ + char buf[PBUFSIZ]; + int i; + char *p; + + if (len > PBUFSIZ / 2 - 1) + abort (); + + sprintf (buf, "m%x,%x", memaddr, len); + remote_send (buf); + + /* Reply describes registers byte by byte, + each byte encoded as two hex characters. */ + + p = buf; + for (i = 0; i < len; i++) + { + if (p[0] == 0 || p[1] == 0) + error ("Remote reply is too short: %s", buf); + myaddr[i] = fromhex (p[0]) * 16 + fromhex (p[1]); + p += 2; + } +} + +/* + +A debug packet whose contents are <data> +is encapsulated for transmission in the form: + + $ <data> # CSUM1 CSUM2 + + <data> must be ASCII alphanumeric and cannot include characters + '$' or '#' + + CSUM1 and CSUM2 are ascii hex representation of an 8-bit + checksum of <data>, the most significant nibble is sent first. + the hex digits 0-9,a-f are used. + +Receiver responds with: + + + - if CSUM is correct and ready for next packet + - - if CSUM is incorrect + +*/ + +/* Send the command in BUF to the remote machine, + and read the reply into BUF. + Report an error if we get an error reply. */ + +static void +remote_send (buf) + char *buf; +{ + int i; + putpkt (buf); + getpkt (buf); + + if (buf[0] == 'E') + error ("Remote failure reply: %s", buf); +} + +/* Send a packet to the remote machine, with error checking. + The data of the packet is in BUF. */ + +static void +putpkt (buf) + char *buf; +{ + int i; + char csum = 0; + char buf2[500]; + char buf3[1]; + int cnt = strlen (buf); + char *p; + + if (kiodebug) + fprintf (stderr, "Sending packet: %s\n", buf); + + /* Copy the packet into buffer BUF2, encapsulating it + and giving it a checksum. */ + + p = buf2; + *p++ = '$'; + + for (i = 0; i < cnt; i++) + { + csum += buf[i]; + *p++ = buf[i]; + } + *p++ = '#'; + *p++ = tohex ((csum >> 4) & 0xf); + *p++ = tohex (csum & 0xf); + + /* Send it over and over until we get a positive ack. */ + + do { + write (remote_desc, buf2, p - buf2); + read (remote_desc, buf3, 1); + } while (buf3[0] != '+'); +} + +static int +readchar () +{ + char buf[1]; + while (read (remote_desc, buf, 1) != 1) ; + return buf[0] & 0x7f; +} + +/* Read a packet from the remote machine, with error checking, + and store it in BUF. */ + +static void +getpkt (buf) + char *buf; +{ + char *bp; + unsigned char csum; + unsigned int c, c1, c2; + extern kiodebug; + + while (1) + { + /* Force csum to be zero here because of possible error retry. */ + csum = 0; + + while ((c = readchar()) != '$'); + + bp = buf; + while (1) + { + c = readchar (); + if (c == '#') + break; + *bp++ = c; + csum += c; + } + *bp = 0; + + c1 = fromhex (readchar ()); + c2 = fromhex (readchar ()); + if (csum == (c1 << 4) + c2) + break; + printf ("Bad checksum, sentsum=0x%x, csum=0x%x, buf=%s\n", + (c1 << 4) + c2, csum, buf); + write (remote_desc, "-", 1); + } + + write (remote_desc, "+", 1); + + if (kiodebug) + fprintf (stderr,"Packet received :%s\n", buf); +} + +/* The data cache records all the data read from the remote machine + since the last time it stopped. + + Each cache block holds 16 bytes of data + starting at a multiple-of-16 address. */ + +#define DCACHE_SIZE 64 /* Number of cache blocks */ + +struct dcache_block { + struct dcache_block *next, *last; + unsigned int addr; /* Address for which data is recorded. */ + int data[4]; +}; + +struct dcache_block dcache_free, dcache_valid; + +/* Free all the data cache blocks, thus discarding all cached data. */ + +static void +dcache_flush () +{ + register struct dcache_block *db; + + while ((db = dcache_valid.next) != &dcache_valid) + { + remque (db); + insque (db, &dcache_free); + } +} + +/* + * If addr is present in the dcache, return the address of the block + * containing it. + */ + +struct dcache_block * +dcache_hit (addr) +{ + register struct dcache_block *db; + + if (addr & 3) + abort (); + + /* Search all cache blocks for one that is at this address. */ + db = dcache_valid.next; + while (db != &dcache_valid) + { + if ((addr & 0xfffffff0) == db->addr) + return db; + db = db->next; + } + return NULL; +} + +/* Return the int data at address ADDR in dcache block DC. */ + +int +dcache_value (db, addr) + struct dcache_block *db; + unsigned int addr; +{ + if (addr & 3) + abort (); + return (db->data[(addr>>2)&3]); +} + +/* Get a free cache block, put it on the valid list, + and return its address. The caller should store into the block + the address and data that it describes. */ + +struct dcache_block * +dcache_alloc () +{ + register struct dcache_block *db; + + if ((db = dcache_free.next) == &dcache_free) + /* If we can't get one from the free list, take last valid */ + db = dcache_valid.last; + + remque (db); + insque (db, &dcache_valid); + return (db); +} + +/* Return the contents of the word at address ADDR in the remote machine, + using the data cache. */ + +int +dcache_fetch (addr) + CORE_ADDR addr; +{ + register struct dcache_block *db; + + db = dcache_hit (addr); + if (db == 0) + { + db = dcache_alloc (); + remote_read_bytes (addr & ~0xf, db->data, 16); + db->addr = addr & ~0xf; + } + return (dcache_value (db, addr)); +} + +/* Write the word at ADDR both in the data cache and in the remote machine. */ + +dcache_poke (addr, data) + CORE_ADDR addr; + int data; +{ + register struct dcache_block *db; + + /* First make sure the word is IN the cache. DB is its cache block. */ + db = dcache_hit (addr); + if (db == 0) + { + db = dcache_alloc (); + remote_read_bytes (addr & ~0xf, db->data, 16); + db->addr = addr & ~0xf; + } + + /* Modify the word in the cache. */ + db->data[(addr>>2)&3] = data; + + /* Send the changed word. */ + remote_write_bytes (addr, &data, 4); +} + +/* Initialize the data cache. */ + +dcache_init () +{ + register i; + register struct dcache_block *db; + + db = (struct dcache_block *) xmalloc (sizeof (struct dcache_block) * + DCACHE_SIZE); + dcache_free.next = dcache_free.last = &dcache_free; + dcache_valid.next = dcache_valid.last = &dcache_valid; + for (i=0;i<DCACHE_SIZE;i++,db++) + insque (db, &dcache_free); +} + +@ + + +1.1 +log +@Initial revision +@ +text +@d74 1 +a74 1 +#include <sys/fcntl.h> +@ |