ref: 17f7f6be4e1a316c0f5f26ff70e047aece4de2bc
dir: /sys/src/libplumb/mesg.c/
#include <u.h> #include <libc.h> #include "plumb.h" int plumbopen(char *name, int omode) { int fd; char buf[128], err[ERRMAX]; if(name[0] == '/') return open(name, omode); if(access("/mnt/plumb/send", AWRITE) < 0) return -1; snprint(buf, sizeof buf, "/mnt/plumb/%s", name); fd = open(buf, omode); if(fd >= 0) return fd; /* try creating port; used by non-standard plumb implementations */ rerrstr(err, sizeof err); fd = create(buf, omode, 0600); if(fd >= 0) return fd; errstr(err, sizeof err); return -1; } static int Strlen(char *s) { if(s == nil) return 0; return strlen(s); } static char* Strcpy(char *s, char *t) { if(t == nil) return s; return strcpy(s, t) + strlen(t); } /* quote attribute value, if necessary */ static char* quote(char *s, char *buf, char *bufe) { char *t; int c; if(s == nil){ buf[0] = '\0'; return buf; } if(strpbrk(s, " '=\t") == nil) return s; t = buf; *t++ = '\''; while(t < bufe-2){ c = *s++; if(c == '\0') break; *t++ = c; if(c == '\'') *t++ = c; } *t++ = '\''; *t = '\0'; return buf; } char* plumbpackattr(Plumbattr *attr) { int n, l; Plumbattr *a; char *s, *t, *buf, *bufe; if(attr == nil) return nil; n = 0; for(a=attr; a!=nil; a=a->next){ l = Strlen(a->value); if(l > n) n = l; } if((buf = malloc(n*2+3)) == nil) return nil; bufe = buf + n*2+3; n = 0; for(a=attr; a!=nil; a=a->next) n += Strlen(a->name) + 1 + Strlen(quote(a->value, buf, bufe)) + 1; s = malloc(n); if(s == nil){ free(buf); return nil; } t = s; *t = '\0'; for(a=attr; a!=nil; a=a->next){ if(t != s) *t++ = ' '; strcpy(t, a->name); strcat(t, "="); strcat(t, quote(a->value, buf, bufe)); t += strlen(t); } if(t > s+n) abort(); free(buf); return s; } char* plumblookup(Plumbattr *attr, char *name) { while(attr){ if(strcmp(attr->name, name) == 0) return attr->value; attr = attr->next; } return nil; } char* plumbpack(Plumbmsg *m, int *np) { int n, ndata; char *buf, *p, *attr; ndata = m->ndata; if(ndata < 0) ndata = Strlen(m->data); attr = plumbpackattr(m->attr); n = Strlen(m->src)+1 + Strlen(m->dst)+1 + Strlen(m->wdir)+1 + Strlen(m->type)+1 + Strlen(attr)+1 + 16 + ndata; buf = malloc(n+1); /* +1 for '\0' */ if(buf == nil){ free(attr); return nil; } p = Strcpy(buf, m->src); *p++ = '\n'; p = Strcpy(p, m->dst); *p++ = '\n'; p = Strcpy(p, m->wdir); *p++ = '\n'; p = Strcpy(p, m->type); *p++ = '\n'; p = Strcpy(p, attr); *p++ = '\n'; p += sprint(p, "%d\n", ndata); memmove(p, m->data, ndata); *np = (p-buf)+ndata; buf[*np] = '\0'; /* null terminate just in case */ if(*np >= n+1) abort(); free(attr); return buf; } int plumbsend(int fd, Plumbmsg *m) { char *buf; int n; buf = plumbpack(m, &n); if(buf == nil) return -1; n = write(fd, buf, n); free(buf); return n; } void plumbfree(Plumbmsg *m) { Plumbattr *a, *next; free(m->src); free(m->dst); free(m->wdir); free(m->type); for(a=m->attr; a!=nil; a=next){ next = a->next; free(a->name); free(a->value); free(a); } free(m->data); free(m); } Plumbattr* plumbunpackattr(char *p) { Plumbattr *attr, *prev, *a; char *q, *v, *buf, *bufe; int c, quoting; c = strlen(p) + 1; if((buf = malloc(c)) == nil) return nil; bufe = buf + c; attr = prev = nil; while(*p!='\0' && *p!='\n'){ while(*p==' ' || *p=='\t') p++; if(*p == '\0') break; for(q=p; *q!='\0' && *q!='\n' && *q!=' ' && *q!='\t'; q++) if(*q == '=') break; if(*q != '=') break; /* malformed attribute */ a = malloc(sizeof(Plumbattr)); if(a == nil) break; a->name = malloc(q-p+1); if(a->name == nil){ free(a); break; } memmove(a->name, p, q-p); a->name[q-p] = '\0'; /* process quotes in value */ q++; /* skip '=' */ v = buf; quoting = 0; while(*q!='\0' && *q!='\n'){ if(v >= bufe) break; c = *q++; if(quoting){ if(c == '\''){ if(*q == '\'') q++; else{ quoting = 0; continue; } } }else{ if(c==' ' || c=='\t') break; if(c == '\''){ quoting = 1; continue; } } *v++ = c; } a->value = malloc(v-buf+1); if(a->value == nil){ free(a->name); free(a); break; } memmove(a->value, buf, v-buf); a->value[v-buf] = '\0'; a->next = nil; if(prev == nil) attr = a; else prev->next = a; prev = a; p = q; } free(buf); return attr; } Plumbattr* plumbaddattr(Plumbattr *attr, Plumbattr *new) { Plumbattr *l; l = attr; if(l == nil) return new; while(l->next != nil) l = l->next; l->next = new; return attr; } Plumbattr* plumbdelattr(Plumbattr *attr, char *name) { Plumbattr *l, *prev; prev = nil; for(l=attr; l!=nil; l=l->next){ if(strcmp(name, l->name) == 0) break; prev = l; } if(l == nil) return nil; if(prev) prev->next = l->next; else attr = l->next; free(l->name); free(l->value); free(l); return attr; } static char* plumbline(char *buf, int *o, int n) { char *p; int i; i = *o; if(i < 0 || i >= n) return nil; p = memchr(buf+i, '\n', n - i); if(p == nil) return nil; n = p - (buf+i); buf = malloc(n+1); if(buf == nil) return nil; memmove(buf, p - n, n); buf[n] = '\0'; *o = i + n+1; return buf; } Plumbmsg* plumbunpackpartial(char *buf, int n, int *morep) { Plumbmsg *m; char *ntext, *attr; int i; if(morep != nil) *morep = 0; m = malloc(sizeof(Plumbmsg)); if(m == nil) return nil; setmalloctag(m, getcallerpc(&buf)); memset(m, 0, sizeof(Plumbmsg)); i = 0; if((m->src = plumbline(buf, &i, n)) == nil) goto bad; if((m->dst = plumbline(buf, &i, n)) == nil) goto bad; if((m->wdir = plumbline(buf, &i, n)) == nil) goto bad; if((m->type = plumbline(buf, &i, n)) == nil) goto bad; if((attr = plumbline(buf, &i, n)) == nil) goto bad; m->attr = plumbunpackattr(attr); free(attr); if((ntext = plumbline(buf, &i, n)) == nil) goto bad; m->ndata = atoi(ntext); free(ntext); if(m->ndata < 0) goto bad; n -= i; if(n < m->ndata){ if(morep != nil) *morep = m->ndata - n; goto bad; } m->data = malloc(m->ndata+1); /* +1 for '\0' */ if(m->data == nil) goto bad; memmove(m->data, buf+i, m->ndata); /* null-terminate in case it's text */ m->data[m->ndata] = '\0'; return m; bad: plumbfree(m); return nil; } Plumbmsg* plumbunpack(char *buf, int n) { Plumbmsg *m; m = plumbunpackpartial(buf, n, nil); if(m != nil) setmalloctag(m, getcallerpc(&buf)); return m; } Plumbmsg* plumbrecv(int fd) { char *buf, *old; Plumbmsg *m; int n, more; buf = malloc(n = 8192); if(buf == nil) return nil; n = read(fd, buf, n); if(n <= 0) m = nil; else { m = plumbunpackpartial(buf, n, &more); if(m == nil && more > 0){ /* we now know how many more bytes to read for complete message */ buf = realloc(old = buf, n+more); if(buf == nil){ free(old); return nil; } if(readn(fd, buf+n, more) == more) m = plumbunpackpartial(buf, n+more, nil); } } free(buf); return m; }