ref: de19776b2f793de7fdf1111d84d96eb29f9a22fd
dir: /sys/src/9/xen/xenstore.c/
#include <u.h> #include <libc.h> typedef ulong uint32_t; enum xsd_sockmsg_type { XS_DEBUG, XS_DIRECTORY, XS_READ, XS_GET_PERMS, XS_WATCH, XS_UNWATCH, XS_TRANSACTION_START, XS_TRANSACTION_END, XS_INTRODUCE, XS_RELEASE, XS_GET_DOMAIN_PATH, XS_WRITE, XS_MKDIR, XS_RM, XS_SET_PERMS, XS_WATCH_EVENT, XS_ERROR, XS_IS_DOMAIN_INTRODUCED }; struct xsd_sockmsg { uint32_t type; /* XS_??? */ uint32_t req_id;/* Request identifier, echoed in daemon's response. */ uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */ uint32_t len; /* Length of data following this. */ /* Generally followed by nul-terminated string(s). */ }; char* xscmd(int fd, enum xsd_sockmsg_type cmd, char *s, char *val) { static char buf[512]; struct xsd_sockmsg *msg; char *arg; static ulong reqid = 1; int n; msg = (struct xsd_sockmsg*)buf; arg = buf + sizeof(*msg); if(cmd != XS_WATCH_EVENT){ msg->type = cmd; msg->req_id = reqid++; msg->tx_id = 0; msg->len = strlen(s)+1; if (val != 0) { msg->len += strlen(val); if (msg->type == XS_WATCH) msg->len++; } strcpy(arg, s); if (val != 0) strcpy(arg+strlen(s)+1, val); if (write(fd, buf, sizeof(*msg)+msg->len) < 0) sysfatal("write: %r"); } if ((n = read(fd, buf, sizeof(*msg))) != sizeof(*msg)) sysfatal("read hdr %d: %r", n); fprint(2, "type %lud req_id %lud len %lud\n", msg->type, msg->req_id, msg->len); if ((n = read(fd, arg, msg->len)) != msg->len) sysfatal("read data %d: %r", n); if (cmd == XS_DIRECTORY || cmd == XS_WATCH_EVENT) { for (s = arg; s < arg+msg->len; s++) { if (*s == 0) *s = ','; else if (*s < 32) *s += '0'; } } arg[msg->len] = 0; return arg; } void usage(void) { sysfatal("Usage: xenstore [lrwdme] path [value]\n"); } void main(int argc, char *argv[]) { int fd; if (argc != 3 && argc != 4) usage(); if(access("/dev/xenstore", AEXIST) < 0) bind("#x", "/dev", MAFTER); fd = open("/dev/xenstore", ORDWR); if (fd < 0) sysfatal("/dev/xenstore: %r"); switch (argv[1][0]) { default: usage(); break; case 'r': print("%s\n", xscmd(fd, XS_READ, argv[2], 0)); break; case 'l': print("%s\n", xscmd(fd, XS_DIRECTORY, argv[2], 0)); break; case 'm': print("%s\n", xscmd(fd, XS_MKDIR, argv[2], 0)); break; case 'd': print("%s\n", xscmd(fd, XS_RM, argv[2], 0)); break; case 'w': if (argc != 4) usage(); print("%s\n", xscmd(fd, XS_WRITE, argv[2], argv[3])); break; case 'e': if (argc != 4) usage(); print("%s\n", xscmd(fd, XS_WATCH, argv[2], argv[3])); close(fd); fd = open("/dev/xenwatch", OREAD); if (fd < 0) sysfatal("/dev/xenwatch: %r"); for (;;) print("%s\n", xscmd(fd, XS_WATCH_EVENT, 0, 0)); } }