X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/d6b2ae5fa68b9a82ffc006c233aef64c5cdb3bd2..9322ba2854211794c27fae9468768b80b767c211:/sbr/m_getfld.c diff --git a/sbr/m_getfld.c b/sbr/m_getfld.c index b0960547..4976b1c5 100644 --- a/sbr/m_getfld.c +++ b/sbr/m_getfld.c @@ -90,7 +90,7 @@ be parsed as well. Unfortunately the speed issue finally caught up with us since this routine is at the very heart of MH. - To speed things up considerably, the routine Eom() was made an auxilary + To speed things up considerably, the routine Eom() was made an auxiliary function called by the macro eom(). Unless we are bursting a maildrop, the eom() macro returns FALSE saying we aren't at the end of the message. @@ -159,7 +159,7 @@ names are typically short (~8 char) and the loop that extracts them might terminate on a colon, newline or max width. I considered using a Vax "scanc" to locate the end of the field followed by a - "bcopy" but the routine call overhead on a Vax is too large for this + "memmove" but the routine call overhead on a Vax is too large for this to work on short names. If Berkeley ever makes "inline" part of the C optimiser (so things like "scanc" turn into inline instructions) a change here would be worthwhile. @@ -175,7 +175,7 @@ so message bodies average at least a few hundred characters. Assuming your system uses reasonably sized stdio buffers (1K or more), this routine should be able to remove the body in large - (>500 byte) chunks. The makes the cost of a call to "bcopy" + (>500 byte) chunks. The makes the cost of a call to "memmove" small but there is a premium on checking for the eom in packed maildrops. The eom pattern is always a simple string so we can construct an efficient pattern matcher for it (e.g., a Vax "matchc" @@ -204,7 +204,6 @@ */ struct m_getfld_state; static int m_Eom (m_getfld_state_t); -static char *matchc(int, char *, int, char *); #define eom(c,s) (s->msg_style != MS_DEFAULT && \ ((c) == *s->msg_delim && m_Eom(s))) @@ -228,7 +227,7 @@ struct m_getfld_state { char *end; /* One past the last character read in. */ /* The following support tracking of the read position in the input file stream so that callers can interleave m_getfld() - calls with ftell() and fseek(). ytes_read replaces the old + calls with ftell() and fseek(). bytes_read replaces the old m_getfld() msg_count global. last_caller_pos is stored when leaving m_getfld()/m_unknown(), then checked on the next entry. last_internal_pos is used to remember the position used @@ -245,10 +244,10 @@ struct m_getfld_state { * The "full" delimiter string for a packed maildrop consists * of a newline followed by the actual delimiter. E.g., the * full string for a Unix maildrop would be: "\n\nFrom ". - * "Fdelim" points to the start of the full string and is used + * "fdelim" points to the start of the full string and is used * in the BODY case of the main routine to search the buffer for * a possible eom. Msg_delim points to the first character of - * the actual delim. string (i.e., fdelim+1). Edelim + * the actual delim. string (i.e., fdelim+1). edelim * points to the 2nd character of actual delimiter string. It * is used in m_Eom because the first character of the string * has been read and matched before m_Eom is called. @@ -268,7 +267,8 @@ void m_getfld_state_init (m_getfld_state_t *gstate, FILE *iob) { m_getfld_state_t s; - s = *gstate = (m_getfld_state_t) mh_xmalloc(sizeof (struct m_getfld_state)); + NEW(s); + *gstate = s; s->readpos = s->end = s->msg_buf; s->bytes_read = s->total_bytes_read = 0; s->last_caller_pos = s->last_internal_pos = 0; @@ -347,7 +347,8 @@ void m_getfld_state_destroy (m_getfld_state_t *gstate) { static void enter_getfld (m_getfld_state_t *gstate, FILE *iob) { m_getfld_state_t s; - off_t pos = ftello (iob); + off_t pos; + off_t pos_movement; if (! *gstate) { m_getfld_state_init (gstate, iob); @@ -363,46 +364,51 @@ enter_getfld (m_getfld_state_t *gstate, FILE *iob) { readpos shift code being currently unused. */ s->iob = iob; - if (s->track_filepos && (pos != 0 || s->last_internal_pos != 0)) { - if (s->last_internal_pos == 0) { - s->total_bytes_read = pos; - } else { - off_t pos_movement = pos - s->last_caller_pos; /* Can be < 0. */ - - if (pos_movement == 0) { - pos = s->last_internal_pos; - } else { - /* The current file stream position differs from the - last one, so caller must have called ftell/o(). - Or, this is the first call and the file position - was not at 0. */ - - if (s->readpos + pos_movement >= s->msg_buf && - s->readpos + pos_movement < s->end) { - /* This is currently unused. It could be used by - parse_mime() if it was changed to use a global - m_getfld_state. */ - /* We can shift readpos and remain within the - bounds of msg_buf. */ - s->readpos += pos_movement; - s->total_bytes_read += pos_movement; - pos = s->last_internal_pos; - } else { - size_t num_read; - - /* This seek skips past an integral number of - chunks of size MSG_INPUT_SIZE. */ - fseeko (iob, pos/MSG_INPUT_SIZE * MSG_INPUT_SIZE, SEEK_SET); - num_read = fread (s->msg_buf, 1, MSG_INPUT_SIZE, iob); - s->readpos = s->msg_buf + pos % MSG_INPUT_SIZE; - s->end = s->msg_buf + num_read; - s->total_bytes_read = pos; - } - } + if (!s->track_filepos) + return; - fseeko (iob, pos, SEEK_SET); - } + pos = ftello(iob); + if (pos == 0 && s->last_internal_pos == 0) + return; + + if (s->last_internal_pos == 0) { + s->total_bytes_read = pos; + return; } + + pos_movement = pos - s->last_caller_pos; /* Can be < 0. */ + if (pos_movement == 0) { + pos = s->last_internal_pos; + } else { + /* The current file stream position differs from the + last one, so caller must have called ftell/o(). + Or, this is the first call and the file position + was not at 0. */ + + if (s->readpos + pos_movement >= s->msg_buf && + s->readpos + pos_movement < s->end) { + /* This is currently unused. It could be used by + parse_mime() if it was changed to use a global + m_getfld_state. */ + /* We can shift readpos and remain within the + bounds of msg_buf. */ + s->readpos += pos_movement; + s->total_bytes_read += pos_movement; + pos = s->last_internal_pos; + } else { + size_t num_read; + + /* This seek skips past an integral number of + chunks of size MSG_INPUT_SIZE. */ + fseeko (iob, pos/MSG_INPUT_SIZE * MSG_INPUT_SIZE, SEEK_SET); + num_read = fread (s->msg_buf, 1, MSG_INPUT_SIZE, iob); + s->readpos = s->msg_buf + pos % MSG_INPUT_SIZE; + s->end = s->msg_buf + num_read; + s->total_bytes_read = pos; + } + } + + fseeko (iob, pos, SEEK_SET); } static void @@ -426,7 +432,8 @@ read_more (m_getfld_state_t s) { ssize_t retain = s->edelimlen; size_t num_read; - if (retain < s->end - s->readpos) retain = s->end - s->readpos; + if (retain < s->end - s->readpos) + retain = s->end - s->readpos; assert (retain <= s->readpos - s->msg_buf); /* Move what we want to retain at end of the buffer to the beginning. */ @@ -444,28 +451,19 @@ read_more (m_getfld_state_t s) { but EOF is typically 0xffffffff. */ static int Getc (m_getfld_state_t s) { - if (s->end - s->readpos < 1) { - if (read_more (s) == 0) { - /* Pretend that we read a character. That's what stdio does. */ - ++s->readpos; - return EOF; - } - } + if ((s->end - s->readpos < 1 && read_more (s) == 0) || + s->readpos >= s->end) + return EOF; - ++s->bytes_read; - return s->readpos < s->end ? (unsigned char) *s->readpos++ : EOF; + s->bytes_read++; + return (unsigned char)*s->readpos++; } static int Peek (m_getfld_state_t s) { - if (s->end - s->readpos < 1) { - if (read_more (s) == 0) { - /* Pretend that we read a character. That's what stdio does. */ - ++s->readpos; - return EOF; - } + if (s->end - s->readpos < 1 && read_more (s) == 0) { + return EOF; } - return s->readpos < s->end ? (unsigned char) *s->readpos : EOF; } @@ -473,10 +471,9 @@ static int Ungetc (int c, m_getfld_state_t s) { if (s->readpos == s->msg_buf) { return EOF; - } else { - --s->bytes_read; - return *--s->readpos = (unsigned char) c; } + --s->bytes_read; + return *--s->readpos = (unsigned char) c; } @@ -485,23 +482,23 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, FILE *iob) { m_getfld_state_t s; - register char *cp; - register int max, n, c; + char *cp; + int max, n, c; enter_getfld (gstate, iob); s = *gstate; - if ((c = Getc(s)) < 0) { + if ((c = Getc(s)) == EOF) { *bufsz = *buf = 0; leave_getfld (s); return s->state = FILEEOF; } if (eom (c, s)) { /* flush null messages */ - while ((c = Getc(s)) >= 0 && eom (c, s)) + while ((c = Getc(s)) != EOF && eom (c, s)) ; - if (c >= 0) + if (c != EOF) Ungetc(c, s); *bufsz = *buf = 0; leave_getfld (s); @@ -512,13 +509,14 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, case FLD: if (c == '\n' || c == '-') { /* we hit the header/body separator */ - while (c != '\n' && (c = Getc(s)) >= 0) continue; + while (c != '\n' && (c = Getc(s)) != EOF) + ; - if (c < 0 || (c = Getc(s)) < 0 || eom (c, s)) { + if (c == EOF || (c = Getc(s)) == EOF || eom (c, s)) { /* flush null messages */ - while ((c = Getc(s)) >= 0 && eom (c, s)) + while ((c = Getc(s)) != EOF && eom (c, s)) ; - if (c >= 0) + if (c != EOF) Ungetc(c, s); *bufsz = *buf = 0; leave_getfld (s); @@ -583,13 +581,17 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, memcpy (buf, name, n - 1); buf[n - 1] = '\n'; buf[n] = '\0'; + /* Indicate this wasn't a header field using a character + that can't appear in a header field. */ + name[0] = ':'; /* The last character read was '\n'. s->bytes_read (and n) include that, but it was not put into the name array in the for loop above. So subtract 1. */ *bufsz = --s->bytes_read; /* == n - 1 */ leave_getfld (s); return s->state = BODY; - } else if (max <= n) { + } + if (max <= n) { /* By design, the loop above discards the last character it had read. It's in c, use it. */ *cp++ = c; @@ -604,7 +606,7 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, while (isspace ((unsigned char) *--cp) && cp >= name) continue; *++cp = 0; /* readpos points to the first character of the field body. */ - /* fall through */ + /* FALLTHRU */ case FLDPLUS: { /* @@ -619,10 +621,12 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, n = 0; for (finished = 0; ! finished; ) { while (c != '\n' && c != EOF && n++ < max) { - if ((c = Getc (s)) != EOF) { *cp++ = c; } + if ((c = Getc (s)) != EOF) + *cp++ = c; } - if (c != EOF) c = Peek (s); + if (c != EOF) + c = Peek (s); if (max < n) { /* The dest buffer is full. Need to back the read pointer up by one because when m_getfld() is @@ -659,6 +663,7 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, */ char *bp; + name[0] = '\0'; max = *bufsz-1; /* Back up and store the current position. */ bp = --s->readpos; @@ -678,7 +683,7 @@ m_getfld (m_getfld_state_t *gstate, char name[NAMESZ], char *buf, int *bufsz, */ char *ep; - if ((ep = matchc( s->fdelimlen, s->fdelim, c, bp ))) + if ((ep = memmem(bp, c, s->fdelim, s->fdelimlen))) c = ep - bp + 1; else { /* @@ -762,11 +767,11 @@ void m_unknown(m_getfld_state_t *gstate, FILE *iob) { m_getfld_state_t s; - register int c; + int c; char text[MAX_DELIMITER_SIZE]; char from[] = "From "; - register char *cp; - register char *delimstr; + char *cp; + char *delimstr; unsigned int i; enter_getfld (gstate, iob); @@ -799,7 +804,8 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob) if (i == sizeof from-1 && strncmp (text, "From ", sizeof from-1) == 0) { s->msg_style = MS_MBOX; delimstr = "\nFrom "; - while ((c = Getc (s)) != '\n' && c >= 0) continue; + while ((c = Getc(s)) != EOF && c != '\n') + ; } else { /* not a Unix style maildrop */ s->readpos -= s->bytes_read; @@ -807,18 +813,32 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob) delimstr = mmdlm2; s->msg_style = MS_MMDF; } + c = strlen (delimstr); - s->fdelim = mh_xmalloc (c + 3); + s->fdelim = mh_xmalloc (c + 3); /* \0, \n, delimstr, \0 */ *s->fdelim++ = '\0'; *s->fdelim = '\n'; - s->msg_delim = s->fdelim+1; - s->edelim = s->msg_delim+1; s->fdelimlen = c + 1; - s->edelimlen = c - 1; /* == strlen (delimstr) */ + s->msg_delim = s->fdelim+1; strcpy (s->msg_delim, delimstr); + s->edelim = s->msg_delim+1; + s->edelimlen = c - 1; s->delimend = s->msg_delim + s->edelimlen; if (s->edelimlen <= 1) adios (NULL, "maildrop delimiter must be at least 2 bytes"); + + /* Now malloc'd memory at s->fdelim-1 referenced several times: + * + * delimstr "\nFrom " "\001\001\001\001\n" + * c 6 5 + * s->fdelim \0"\n\nFrom " \0"\n\001\001\001\001\n" + * s->fdelimlen 6 5 + * s->msg_delim "\nFrom " "\001\001\001\001\n" + * s->edelim "From " "\001\001\001\n" + * s->edelimlen 5 4 + * s->delimend " " "\n" + */ + /* * build a Boyer-Moore end-position map for the matcher in m_getfld. * N.B. - we don't match just the first char (since it's the newline @@ -832,9 +852,9 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob) if (s->msg_style == MS_MMDF) { /* flush extra msg hdrs */ - while ((c = Getc(s)) >= 0 && eom (c, s)) + while ((c = Getc(s)) != EOF && eom (c, s)) ; - if (c >= 0) + if (c != EOF) Ungetc(c, s); } @@ -849,7 +869,7 @@ m_unknown(m_getfld_state_t *gstate, FILE *iob) static int m_Eom (m_getfld_state_t s) { - register int i; + int i; char text[MAX_DELIMITER_SIZE]; char *cp; @@ -882,34 +902,9 @@ m_Eom (m_getfld_state_t s) if (s->msg_style == MS_MBOX) { int c; - while ((c = Getc (s)) != '\n') - if (c < 0) - break; + while ((c = Getc(s)) != EOF && c != '\n') + ; } return 1; } - - -static char * -matchc(int patln, char *pat, int strln, char *str) -{ - register char *es = str + strln - patln; - register char *sp; - register char *pp; - register char *ep = pat + patln; - register char pc = *pat++; - - for(;;) { - while (pc != *str++) - if (str > es) - return 0; - if (str > es+1) - return 0; - sp = str; pp = pat; - while (pp < ep && *sp++ == *pp) - pp++; - if (pp >= ep) - return --str; - } -}