/* $OpenBSD: shf.c,v 1.24 2015/10/19 14:03:21 mmcc Exp $ */ /* * Shell file I/O routines */ #include #include #include "sh.h" /* flags to shf_emptybuf() */ #define EB_READSW 0x01 /* about to switch to reading */ #define EB_GROW 0x02 /* grow buffer if necessary (STRING+DYNAMIC) */ /* * Replacement stdio routines. Stdio is too flakey on too many machines * to be useful when you have multiple processes using the same underlying * file descriptors. */ static int shf_fillbuf(struct shf *); static int shf_emptybuf(struct shf *, int); /* Open a file. First three args are for open(), last arg is flags for * this package. Returns NULL if file could not be opened, or if a dup * fails. */ struct shf * shf_open(const char *name, int oflags, int mode, int sflags) { struct shf *shf; int bsize = sflags & SHF_UNBUF ? (sflags & SHF_RD ? 1 : 0) : SHF_BSIZE; int fd; /* Done before open so if alloca fails, fd won't be lost. */ shf = alloc(sizeof(struct shf) + bsize, ATEMP); shf->areap = ATEMP; shf->buf = (unsigned char *) &shf[1]; shf->bsize = bsize; shf->flags = SHF_ALLOCS; /* Rest filled in by reopen. */ fd = open(name, oflags, mode); if (fd < 0) { afree(shf, shf->areap); return NULL; } if ((sflags & SHF_MAPHI) && fd < FDBASE) { int nfd; nfd = fcntl(fd, F_DUPFD, FDBASE); close(fd); if (nfd < 0) { afree(shf, shf->areap); return NULL; } fd = nfd; } sflags &= ~SHF_ACCMODE; sflags |= (oflags & O_ACCMODE) == O_RDONLY ? SHF_RD : ((oflags & O_ACCMODE) == O_WRONLY ? SHF_WR : SHF_RDWR); return shf_reopen(fd, sflags, shf); } /* Set up the shf structure for a file descriptor. Doesn't fail. */ struct shf * shf_fdopen(int fd, int sflags, struct shf *shf) { int bsize = sflags & SHF_UNBUF ? (sflags & SHF_RD ? 1 : 0) : SHF_BSIZE; /* use fcntl() to figure out correct read/write flags */ if (sflags & SHF_GETFL) { int flags = fcntl(fd, F_GETFL, 0); if (flags < 0) /* will get an error on first read/write */ sflags |= SHF_RDWR; else { switch (flags & O_ACCMODE) { case O_RDONLY: sflags |= SHF_RD; break; case O_WRONLY: sflags |= SHF_WR; break; case O_RDWR: sflags |= SHF_RDWR; break; } } } if (!(sflags & (SHF_RD | SHF_WR))) internal_errorf(1, "shf_fdopen: missing read/write"); if (shf) { if (bsize) { shf->buf = alloc(bsize, ATEMP); sflags |= SHF_ALLOCB; } else shf->buf = NULL; } else { shf = alloc(sizeof(struct shf) + bsize, ATEMP); shf->buf = (unsigned char *) &shf[1]; sflags |= SHF_ALLOCS; } shf->areap = ATEMP; shf->fd = fd; shf->rp = shf->wp = shf->buf; shf->rnleft = 0; shf->rbsize = bsize; shf->wnleft = 0; /* force call to shf_emptybuf() */ shf->wbsize = sflags & SHF_UNBUF ? 0 : bsize; shf->flags = sflags; shf->errno_ = 0; shf->bsize = bsize; if (sflags & SHF_CLEXEC) fcntl(fd, F_SETFD, FD_CLOEXEC); return shf; } /* Set up an existing shf (and buffer) to use the given fd */ struct shf * shf_reopen(int fd, int sflags, struct shf *shf) { int bsize = sflags & SHF_UNBUF ? (sflags & SHF_RD ? 1 : 0) : SHF_BSIZE; /* use fcntl() to figure out correct read/write flags */ if (sflags & SHF_GETFL) { int flags = fcntl(fd, F_GETFL, 0); if (flags < 0) /* will get an error on first read/write */ sflags |= SHF_RDWR; else { switch (flags & O_ACCMODE) { case O_RDONLY: sflags |= SHF_RD; break; case O_WRONLY: sflags |= SHF_WR; break; case O_RDWR: sflags |= SHF_RDWR; break; } } } if (!(sflags & (SHF_RD | SHF_WR))) internal_errorf(1, "shf_reopen: missing read/write"); if (!shf || !shf->buf || shf->bsize < bsize) internal_errorf(1, "shf_reopen: bad shf/buf/bsize"); /* assumes shf->buf and shf->bsize already set up */ shf->fd = fd; shf->rp = shf->wp = shf->buf; shf->rnleft = 0; shf->rbsize = bsize; shf->wnleft = 0; /* force call to shf_emptybuf() */ shf->wbsize = sflags & SHF_UNBUF ? 0 : bsize; shf->flags = (shf->flags & (SHF_ALLOCS | SHF_ALLOCB)) | sflags; shf->errno_ = 0; if (sflags & SHF_CLEXEC) fcntl(fd, F_SETFD, FD_CLOEXEC); return shf; } /* Open a string for reading or writing. If reading, bsize is the number * of bytes that can be read. If writing, bsize is the maximum number of * bytes that can be written. If shf is not null, it is filled in and * returned, if it is null, shf is allocated. If writing and buf is null * and SHF_DYNAMIC is set, the buffer is allocated (if bsize > 0, it is * used for the initial size). Doesn't fail. * When writing, a byte is reserved for a trailing null - see shf_sclose(). */ struct shf * shf_sopen(char *buf, int bsize, int sflags, struct shf *shf) { /* can't have a read+write string */ if (!(sflags & (SHF_RD | SHF_WR)) || (sflags & (SHF_RD | SHF_WR)) == (SHF_RD | SHF_WR)) internal_errorf(1, "shf_sopen: flags 0x%x", sflags); if (!shf) { shf = alloc(sizeof(struct shf), ATEMP); sflags |= SHF_ALLOCS; } shf->areap = ATEMP; if (!buf && (sflags & SHF_WR) && (sflags & SHF_DYNAMIC)) { if (bsize <= 0) bsize = 64; sflags |= SHF_ALLOCB; buf = alloc(bsize, shf->areap); } shf->fd = -1; shf->buf = shf->rp = shf->wp = (unsigned char *) buf; shf->rnleft = bsize; shf->rbsize = bsize; shf->wnleft = bsize - 1; /* space for a '\0' */ shf->wbsize = bsize; shf->flags = sflags | SHF_STRING; shf->errno_ = 0; shf->bsize = bsize; return shf; } /* Flush and close file descriptor, free the shf structure */ int shf_close(struct shf *shf) { int ret = 0; if (shf->fd >= 0) { ret = shf_flush(shf); if (close(shf->fd) < 0) ret = EOF; } if (shf->flags & SHF_ALLOCS) afree(shf, shf->areap); else if (shf->flags & SHF_ALLOCB) afree(shf->buf, shf->areap); return ret; } /* Flush and close file descriptor, don't free file structure */ int shf_fdclose(struct shf *shf) { int ret = 0; if (shf->fd >= 0) { ret = shf_flush(shf); if (close(shf->fd) < 0) ret = EOF; shf->rnleft = 0; shf->rp = shf->buf; shf->wnleft = 0; shf->fd = -1; } return ret; } /* Close a string - if it was opened for writing, it is null terminated; * returns a pointer to the string and frees shf if it was allocated * (does not free string if it was allocated). */ char * shf_sclose(struct shf *shf) { unsigned char *s = shf->buf; /* null terminate */ if (shf->flags & SHF_WR) { shf->wnleft++; shf_putc('\0', shf); } if (shf->flags & SHF_ALLOCS) afree(shf, shf->areap); return (char *) s; } /* Un-read what has been read but not examined, or write what has been * buffered. Returns 0 for success, EOF for (write) error. */ int shf_flush(struct shf *shf) { if (shf->flags & SHF_STRING) return (shf->flags & SHF_WR) ? EOF : 0; if (shf->fd < 0) internal_errorf(1, "shf_flush: no fd"); if (shf->flags & SHF_ERROR) { errno = shf->errno_; return EOF; } if (shf->flags & SHF_READING) { shf->flags &= ~(SHF_EOF | SHF_READING); if (shf->rnleft > 0) { lseek(shf->fd, (off_t) -shf->rnleft, SEEK_CUR); shf->rnleft = 0; shf->rp = shf->buf; } return 0; } else if (shf->flags & SHF_WRITING) return shf_emptybuf(shf, 0); return 0; } /* Write out any buffered data. If currently reading, flushes the read * buffer. Returns 0 for success, EOF for (write) error. */ static int shf_emptybuf(struct shf *shf, int flags) { int ret = 0; if (!(shf->flags & SHF_STRING) && shf->fd < 0) internal_errorf(1, "shf_emptybuf: no fd"); if (shf->flags & SHF_ERROR) { errno = shf->errno_; return EOF; } if (shf->flags & SHF_READING) { if (flags & EB_READSW) /* doesn't happen */ return 0; ret = shf_flush(shf); shf->flags &= ~SHF_READING; } if (shf->flags & SHF_STRING) { unsigned char *nbuf; /* Note that we assume SHF_ALLOCS is not set if SHF_ALLOCB * is set... (changing the shf pointer could cause problems) */ if (!(flags & EB_GROW) || !(shf->flags & SHF_DYNAMIC) || !(shf->flags & SHF_ALLOCB)) return EOF; /* allocate more space for buffer */ nbuf = (unsigned char *) aresize(shf->buf, shf->wbsize * 2, shf->areap); shf->rp = nbuf + (shf->rp - shf->buf); shf->wp = nbuf + (shf->wp - shf->buf); shf->rbsize += shf->wbsize; shf->wnleft += shf->wbsize; shf->wbsize *= 2; shf->buf = nbuf; } else { if (shf->flags & SHF_WRITING) { int ntowrite = shf->wp - shf->buf; unsigned char *buf = shf->buf; int n; while (ntowrite > 0) { n = write(shf->fd, buf, ntowrite); if (n < 0) { if (errno == EINTR && !(shf->flags & SHF_INTERRUPT)) continue; shf->flags |= SHF_ERROR; shf->errno_ = errno; shf->wnleft = 0; if (buf != shf->buf) { /* allow a second flush * to work */ memmove(shf->buf, buf, ntowrite); shf->wp = shf->buf + ntowrite; } return EOF; } buf += n; ntowrite -= n; } if (flags & EB_READSW) { shf->wp = shf->buf; shf->wnleft = 0; shf->flags &= ~SHF_WRITING; return 0; } } shf->wp = shf->buf; shf->wnleft = shf->wbsize; } shf->flags |= SHF_WRITING; return ret; } /* Fill up a read buffer. Returns EOF for a read error, 0 otherwise. */ static int shf_fillbuf(struct shf *shf) { if (shf->flags & SHF_STRING) return 0; if (shf->fd < 0) internal_errorf(1, "shf_fillbuf: no fd"); if (shf->flags & (SHF_EOF | SHF_ERROR)) { if (shf->flags & SHF_ERROR) errno = shf->errno_; return EOF; } if ((shf->flags & SHF_WRITING) && shf_emptybuf(shf, EB_READSW) == EOF) return EOF; shf->flags |= SHF_READING; shf->rp = shf->buf; while (1) { shf->rnleft = blocking_read(shf->fd, (char *) shf->buf, shf->rbsize); if (shf->rnleft < 0 && errno == EINTR && !(shf->flags & SHF_INTERRUPT)) continue; break; } if (shf->rnleft <= 0) { if (shf->rnleft < 0) { shf->flags |= SHF_ERROR; shf->errno_ = errno; shf->rnleft = 0; shf->rp = shf->buf; return EOF; } shf->flags |= SHF_EOF; } return 0; } /* Read a buffer from shf. Returns the number of bytes read into buf, * if no bytes were read, returns 0 if end of file was seen, EOF if * a read error occurred. */ int shf_read(char *buf, int bsize, struct shf *shf) { int orig_bsize = bsize; int ncopy; if (!(shf->flags & SHF_RD)) internal_errorf(1, "shf_read: flags %x", shf->flags); if (bsize <= 0) internal_errorf(1, "shf_read: bsize %d", bsize); while (bsize > 0) { if (shf->rnleft == 0 && (shf_fillbuf(shf) == EOF || shf->rnleft == 0)) break; ncopy = shf->rnleft; if (ncopy > bsize) ncopy = bsize; memcpy(buf, shf->rp, ncopy); buf += ncopy; bsize -= ncopy; shf->rp += ncopy; shf->rnleft -= ncopy; } /* Note: fread(3S) returns 0 for errors - this doesn't */ return orig_bsize == bsize ? (shf_error(shf) ? EOF : 0) : orig_bsize - bsize; } /* Read up to a newline or EOF. The newline is put in buf; buf is always * null terminated. Returns NULL on read error or if nothing was read before * end of file, returns a pointer to the null byte in buf otherwise. */ char * shf_getse(char *buf, int bsize, struct shf *shf) { unsigned char *end; int ncopy; char *orig_buf = buf; if (!(shf->flags & SHF_RD)) internal_errorf(1, "shf_getse: flags %x", shf->flags); if (bsize <= 0) return NULL; --bsize; /* save room for null */ do { if (shf->rnleft == 0) { if (shf_fillbuf(shf) == EOF) return NULL; if (shf->rnleft == 0) { *buf = '\0'; return buf == orig_buf ? NULL : buf; } } end = (unsigned char *) memchr((char *) shf->rp, '\n', shf->rnleft); ncopy = end ? end - shf->rp + 1 : shf->rnleft; if (ncopy > bsize) ncopy = bsize; memcpy(buf, (char *) shf->rp, ncopy); shf->rp += ncopy; shf->rnleft -= ncopy; buf += ncopy; bsize -= ncopy; } while (!end && bsize); *buf = '\0'; return buf; } /* Returns the char read. Returns EOF for error and end of file. */ int shf_getchar(struct shf *shf) { if (!(shf->flags & SHF_RD)) internal_errorf(1, "shf_getchar: flags %x", shf->flags); if (shf->rnleft == 0 && (shf_fillbuf(shf) == EOF || shf->rnleft == 0)) return EOF; --shf->rnleft; return *shf->rp++; } /* Put a character back in the input stream. Returns the character if * successful, EOF if there is no room. */ int shf_ungetc(int c, struct shf *shf) { if (!(shf->flags & SHF_RD)) internal_errorf(1, "shf_ungetc: flags %x", shf->flags); if ((shf->flags & SHF_ERROR) || c == EOF || (shf->rp == shf->buf && shf->rnleft)) return EOF; if ((shf->flags & SHF_WRITING) && shf_emptybuf(shf, EB_READSW) == EOF) return EOF; if (shf->rp == shf->buf) shf->rp = shf->buf + shf->rbsize; if (shf->flags & SHF_STRING) { /* Can unget what was read, but not something different - we * don't want to modify a string. */ if (shf->rp[-1] != c) return EOF; shf->flags &= ~SHF_EOF; shf->rp--; shf->rnleft++; return c; } shf->flags &= ~SHF_EOF; *--(shf->rp) = c; shf->rnleft++; return c; } /* Write a character. Returns the character if successful, EOF if * the char could not be written. */ int shf_putchar(int c, struct shf *shf) { if (!(shf->flags & SHF_WR)) internal_errorf(1, "shf_putchar: flags %x", shf->flags); if (c == EOF) return EOF; if (shf->flags & SHF_UNBUF) { char cc = c; int n; if (shf->fd < 0) internal_errorf(1, "shf_putchar: no fd"); if (shf->flags & SHF_ERROR) { errno = shf->errno_; return EOF; } while ((n = write(shf->fd, &cc, 1)) != 1) if (n < 0) { if (errno == EINTR && !(shf->flags & SHF_INTERRUPT)) continue; shf->flags |= SHF_ERROR; shf->errno_ = errno; return EOF; } } else { /* Flush deals with strings and sticky errors */ if (shf->wnleft == 0 && shf_emptybuf(shf, EB_GROW) == EOF) return EOF; shf->wnleft--; *shf->wp++ = c; } return c; } /* Write a string. Returns the length of the string if successful, EOF if * the string could not be written. */ int shf_puts(const char *s, struct shf *shf) { if (!s) return EOF; return shf_write(s, strlen(s), shf); } /* Write a buffer. Returns nbytes if successful, EOF if there is an error. */ int shf_write(const char *buf, int nbytes, struct shf *shf) { int orig_nbytes = nbytes; int n; int ncopy; if (!(shf->flags & SHF_WR)) internal_errorf(1, "shf_write: flags %x", shf->flags); if (nbytes < 0) internal_errorf(1, "shf_write: nbytes %d", nbytes); /* Don't buffer if buffer is empty and we're writting a large amount. */ if ((ncopy = shf->wnleft) && (shf->wp != shf->buf || nbytes < shf->wnleft)) { if (ncopy > nbytes) ncopy = nbytes; memcpy(shf->wp, buf, ncopy); nbytes -= ncopy; buf += ncopy; shf->wp += ncopy; shf->wnleft -= ncopy; } if (nbytes > 0) { /* Flush deals with strings and sticky errors */ if (shf_emptybuf(shf, EB_GROW) == EOF) return EOF; if (nbytes > shf->wbsize) { ncopy = nbytes; if (shf->wbsize) ncopy -= nbytes % shf->wbsize; nbytes -= ncopy; while (ncopy > 0) { n = write(shf->fd, buf, ncopy); if (n < 0) { if (errno == EINTR && !(shf->flags & SHF_INTERRUPT)) continue; shf->flags |= SHF_ERROR; shf->errno_ = errno; shf->wnleft = 0; /* Note: fwrite(3S) returns 0 for * errors - this doesn't */ return EOF; } buf += n; ncopy -= n; } } if (nbytes > 0) { memcpy(shf->wp, buf, nbytes); shf->wp += nbytes; shf->wnleft -= nbytes; } } return orig_nbytes; } int shf_fprintf(struct shf *shf, const char *fmt, ...) { va_list args; int n; va_start(args, fmt); n = shf_vfprintf(shf, fmt, args); va_end(args); return n; } int shf_snprintf(char *buf, int bsize, const char *fmt, ...) { struct shf shf; va_list args; int n; if (!buf || bsize <= 0) internal_errorf(1, "shf_snprintf: buf %lx, bsize %d", (long) buf, bsize); shf_sopen(buf, bsize, SHF_WR, &shf); va_start(args, fmt); n = shf_vfprintf(&shf, fmt, args); va_end(args); shf_sclose(&shf); /* null terminates */ return n; } char * shf_smprintf(const char *fmt, ...) { struct shf shf; va_list args; shf_sopen(NULL, 0, SHF_WR|SHF_DYNAMIC, &shf); va_start(args, fmt); shf_vfprintf(&shf, fmt, args); va_end(args); return shf_sclose(&shf); /* null terminates */ } #define BUF_SIZE 128 #define ABIGNUM 32000 /* big number that will fit in a short */ #define LOG2_10 3.321928094887362347870319429 /* log base 2 of 10 */ #define FL_HASH 0x001 /* `#' seen */ #define FL_PLUS 0x002 /* `+' seen */ #define FL_RIGHT 0x004 /* `-' seen */ #define FL_BLANK 0x008 /* ` ' seen */ #define FL_SHORT 0x010 /* `h' seen */ #define FL_LONG 0x020 /* `l' seen */ #define FL_LLONG 0x040 /* `ll' seen */ #define FL_ZERO 0x080 /* `0' seen */ #define FL_DOT 0x100 /* '.' seen */ #define FL_UPPER 0x200 /* format character was uppercase */ #define FL_NUMBER 0x400 /* a number was formated %[douxefg] */ int shf_vfprintf(struct shf *shf, const char *fmt, va_list args) { char c, *s; int tmp = 0; int field, precision; int len; int flags; unsigned long long llnum; /* %#o produces the longest output */ char numbuf[(BITS(long long) + 2) / 3 + 1]; /* this stuff for dealing with the buffer */ int nwritten = 0; if (!fmt) return 0; while ((c = *fmt++)) { if (c != '%') { shf_putc(c, shf); nwritten++; continue; } /* * This will accept flags/fields in any order - not * just the order specified in printf(3), but this is * the way _doprnt() seems to work (on bsd and sysV). * The only restriction is that the format character must * come last :-). */ flags = field = precision = 0; for ( ; (c = *fmt++) ; ) { switch (c) { case '#': flags |= FL_HASH; continue; case '+': flags |= FL_PLUS; continue; case '-': flags |= FL_RIGHT; continue; case ' ': flags |= FL_BLANK; continue; case '0': if (!(flags & FL_DOT)) flags |= FL_ZERO; continue; case '.': flags |= FL_DOT; precision = 0; continue; case '*': tmp = va_arg(args, int); if (flags & FL_DOT) precision = tmp; else if ((field = tmp) < 0) { field = -field; flags |= FL_RIGHT; } continue; case 'l': if (*fmt == 'l') { fmt++; flags |= FL_LLONG; } else flags |= FL_LONG; continue; case 'h': flags |= FL_SHORT; continue; } if (digit(c)) { tmp = c - '0'; while (c = *fmt++, digit(c)) tmp = tmp * 10 + c - '0'; --fmt; if (tmp < 0) /* overflow? */ tmp = 0; if (flags & FL_DOT) precision = tmp; else field = tmp; continue; } break; } if (precision < 0) precision = 0; if (!c) /* nasty format */ break; if (c >= 'A' && c <= 'Z') { flags |= FL_UPPER; c = c - 'A' + 'a'; } switch (c) { case 'p': /* pointer */ flags &= ~(FL_LLONG | FL_SHORT); flags |= FL_LONG; /* aaahhh... */ case 'd': case 'i': case 'o': case 'u': case 'x': flags |= FL_NUMBER; s = &numbuf[sizeof(numbuf)]; if (flags & FL_LLONG) llnum = va_arg(args, unsigned long long); else if (flags & FL_LONG) { if (c == 'd' || c == 'i') llnum = va_arg(args, long); else llnum = va_arg(args, unsigned long); } else { if (c == 'd' || c == 'i') llnum = va_arg(args, int); else llnum = va_arg(args, unsigned int); } switch (c) { case 'd': case 'i': if (0 > (long long) llnum) llnum = - (long long) llnum, tmp = 1; else tmp = 0; /* aaahhhh..... */ case 'u': do { *--s = llnum % 10 + '0'; llnum /= 10; } while (llnum); if (c != 'u') { if (tmp) *--s = '-'; else if (flags & FL_PLUS) *--s = '+'; else if (flags & FL_BLANK) *--s = ' '; } break; case 'o': do { *--s = (llnum & 0x7) + '0'; llnum >>= 3; } while (llnum); if ((flags & FL_HASH) && *s != '0') *--s = '0'; break; case 'p': case 'x': { const char *digits = (flags & FL_UPPER) ? "0123456789ABCDEF" : "0123456789abcdef"; do { *--s = digits[llnum & 0xf]; llnum >>= 4; } while (llnum); if (flags & FL_HASH) { *--s = (flags & FL_UPPER) ? 'X' : 'x'; *--s = '0'; } } } len = &numbuf[sizeof(numbuf)] - s; if (flags & FL_DOT) { if (precision > len) { field = precision; flags |= FL_ZERO; } else precision = len; /* no loss */ } break; case 's': if (!(s = va_arg(args, char *))) s = "(null %s)"; len = strlen(s); break; case 'c': flags &= ~FL_DOT; numbuf[0] = va_arg(args, int); s = numbuf; len = 1; break; case '%': default: numbuf[0] = c; s = numbuf; len = 1; break; } /* * At this point s should point to a string that is * to be formatted, and len should be the length of the * string. */ if (!(flags & FL_DOT) || len < precision) precision = len; if (field > precision) { field -= precision; if (!(flags & FL_RIGHT)) { field = -field; /* skip past sign or 0x when padding with 0 */ if ((flags & FL_ZERO) && (flags & FL_NUMBER)) { if (*s == '+' || *s == '-' || *s ==' ') { shf_putc(*s, shf); s++; precision--; nwritten++; } else if (*s == '0') { shf_putc(*s, shf); s++; nwritten++; if (--precision > 0 && (*s | 0x20) == 'x') { shf_putc(*s, shf); s++; precision--; nwritten++; } } c = '0'; } else c = flags & FL_ZERO ? '0' : ' '; if (field < 0) { nwritten += -field; for ( ; field < 0 ; field++) shf_putc(c, shf); } } else c = ' '; } else field = 0; if (precision > 0) { nwritten += precision; for ( ; precision-- > 0 ; s++) shf_putc(*s, shf); } if (field > 0) { nwritten += field; for ( ; field > 0 ; --field) shf_putc(c, shf); } } return shf_error(shf) ? EOF : nwritten; }