various code that may end up as a mail client

1 files changed, 373 insertions, 0 deletions

diff --git a/blaze822.c b/blaze822.c
new file mode 100644
index 0000000..11b5285
--- /dev/null
+++ b/blaze822.c
@@ -0,0 +1,373 @@
+// memmem
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <string.h>
+#include <errno.h>
+#include <time.h>
+
+//          WSP            =  SP / HTAB
+#define iswsp(c)  (((c) == ' ' || (c) == '\t'))
+
+#define bufsiz 4096
+
+static long
+parse_posint(char **s, size_t minn, size_t maxn)
+{
+        long n;
+        char *end;
+
+        errno = 0;
+        n = strtol(*s, &end, 10);
+        if (errno) {
+//                perror("strtol");
+		return -1;
+        }
+        if (n < (long)minn || n > (long)maxn) {
+//                fprintf(stderr, "number outside %zd <= n < %zd\n", minn, maxn);
+		return -1;
+        }
+        *s = end;
+        return n;
+}
+
+time_t
+parse_date(char *s) {
+	struct tm tm;
+	int c;
+
+#if 0
+#define i4(m) (s[0] && (s[0]|0x20) == m[0] && \
+               s[1] && (s[1]|0x20) == m[1] && \
+               s[2] && (s[2]|0x20) == m[2] && \
+               s[3] && (s[3]|0x20) == m[3] && (s = s+4) )
+
+#define i3(m) (s[0] && (s[0]|0x20) == m[0] && \
+               s[1] && (s[1]|0x20) == m[1] && \
+               s[2] && (s[2]|0x20) == m[2] && (s = s+3) )
+#endif
+
+#define i4(m) (((uint32_t) m[0]<<24 | m[1]<<16 | m[2]<<8 | m[3]) == \
+	       ((uint32_t) s[0]<<24 | s[1]<<16 | s[2]<<8 | s[3] | 0x20202020) \
+	       && (s += 4))
+
+#define i3(m) (((uint32_t) m[0]<<24 | m[1]<<16 | m[2]<<8) == \
+	       ((uint32_t) s[0]<<24 | s[1]<<16 | s[2]<<8 | 0x20202000) \
+	       && (s += 3))
+
+	while (iswsp(*s))
+		s++;
+	if (i4("mon,") || i4("tue,") || i4("wed,") || i4("thu,") ||
+	    i4("fri,") || i4("sat,") || i4("sun,"))
+		while (iswsp(*s))
+			s++;
+
+	if ((c = parse_posint(&s, 1, 31)) < 0) goto fail;
+	tm.tm_mday = c;
+
+	while (iswsp(*s))
+		s++;
+	
+	if      (i3("jan")) tm.tm_mon = 0;
+	else if (i3("feb")) tm.tm_mon = 1;
+	else if (i3("mar")) tm.tm_mon = 2;
+	else if (i3("apr")) tm.tm_mon = 3;
+	else if (i3("may")) tm.tm_mon = 4;
+	else if (i3("jul")) tm.tm_mon = 5;
+	else if (i3("jun")) tm.tm_mon = 6;
+	else if (i3("aug")) tm.tm_mon = 7;
+	else if (i3("sep")) tm.tm_mon = 8;
+	else if (i3("oct")) tm.tm_mon = 9;
+	else if (i3("nov")) tm.tm_mon = 10;
+	else if (i3("dec")) tm.tm_mon = 11;
+	else goto fail;
+
+	while (iswsp(*s))
+		s++;
+	
+	if ((c = parse_posint(&s, 1000, 9999)) > 0) {
+		tm.tm_year = c - 1900;
+	} else if ((c = parse_posint(&s, 0, 49)) > 0) {
+		tm.tm_year = c + 100;
+	} else if ((c = parse_posint(&s, 50, 99)) > 0) {
+		tm.tm_year = c;
+	} else goto fail;
+
+	while (iswsp(*s))
+		s++;
+
+	if ((c = parse_posint(&s, 0, 24)) < 0) goto fail;
+	tm.tm_hour = c;
+	if (*s++ != ':') goto fail;
+	if ((c = parse_posint(&s, 0, 59)) < 0) goto fail;
+	tm.tm_min = c;
+	if (*s++ == ':') {
+		if ((c = parse_posint(&s, 0, 61)) < 0) goto fail;
+		tm.tm_sec = c;
+	}
+
+	while (iswsp(*s))
+		s++;
+
+	if (*s == '+' || *s == '-') {
+		int neg = (*s == '-');
+		s++;
+		if ((c = parse_posint(&s, 0, 10000)) < 0) goto fail;
+		if (neg) {
+                        tm.tm_hour += c / 100;
+                        tm.tm_min  += c % 100;
+		} else {
+                        tm.tm_hour -= c / 100;
+                        tm.tm_min  -= c % 100;
+                }
+	}
+
+	tm.tm_isdst = -1;
+
+	time_t r = mktime(&tm);
+	return r;
+
+fail:
+	return -1;
+}
+
+char *
+parse_addr(char *s, char **dispo, char **addro)
+{
+	static char disp[1024];
+	static char addr[1024];
+//	char *disp = disp+sizeof disp;
+//	char *addr = addr+sizeof addr;
+	char *c, *e;
+
+	printf("RAW : |%s|\n", s);
+	
+	while (iswsp(*s))
+		s++;
+	
+	c = disp;
+	e = disp + sizeof disp;
+
+	*disp = 0;
+	*addr = 0;
+
+	while (*s) {
+		if (*s == '<') {
+			char *c = addr;
+			char *e = addr + sizeof addr;
+
+			s++;
+			while (*s && c < e && *s != '>')
+				*c++ = *s++;
+			if (*s == '>')
+				s++;
+			*c = 0;
+		} else if (*s == '"') {
+			s++;
+			while (*s && c < e && *s != '"')
+				*c++ = *s++;
+			if (*s == '"')
+				s++;
+		} else if (*s == '(') {
+			s++;
+
+			if (!*addr) {   // assume: user@host (name)
+				*c-- = 0;
+				while (c > disp && iswsp(*c))
+					*c-- = 0;
+				strcpy(addr, disp);
+				c = disp;
+				*c = 0;
+			}
+
+			while (*s && c < e && *s != ')')
+				*c++ = *s++;
+			if (*s == ')')
+				s++;
+		} else if (*s == ',') {
+			s++;
+			break;
+		} else {
+			*c++ = *s++;
+		}
+	}
+
+	*c-- = 0;
+	// strip trailing ws
+	while (c > disp && iswsp(*c))
+		*c-- = 0;
+
+	if (*disp && !*addr && strchr(disp, '@')) {
+		// just mail address was given
+		strcpy(addr, disp);
+		*disp = 0;
+	}
+
+	printf("DISP :: |%s|\n", disp);
+	printf("ADDR :: |%s|\n", addr);
+
+	if (dispo) *dispo = disp;
+	if (addro) *addro = addr;
+
+	return s;
+}
+
+void
+blaze822(char *file)
+{
+	int fd;
+	ssize_t rd;
+	char *buf;
+	ssize_t bufalloc;
+	ssize_t used;
+	char *end;
+
+	fd = open(file, O_RDONLY);
+	if (fd < 0) {
+		perror("open");
+		return;
+	}
+
+	buf = malloc(3);
+	buf[0] = '\n';
+	buf[1] = '\n';
+	buf[2] = '\n';
+	bufalloc = 3;
+	used = 3;
+
+	while (1) {
+		bufalloc += bufsiz;
+		buf = realloc(buf, bufalloc);
+
+		rd = read(fd, buf+used, bufalloc-used);
+		if (rd == 0) {
+			end = buf+used;
+			break;
+		}
+		if (rd < 0)
+			exit(-1);
+
+		if ((end = memmem(buf-1+used, rd+1, "\n\n", 2)) ||
+		    (end = memmem(buf-3+used, rd+3, "\r\n\r\n", 4))) {
+			used += rd;
+			break;
+		}
+
+		used += rd;
+	}
+	close(fd);
+
+	end++;
+	*end = 0;   // dereferencing *end is safe
+
+	char *s;
+	for (s = buf; s < end; s++) {
+		if (*s == 0)   // sanitize nul bytes in headers
+			*s = ' ';
+
+		if (*s == '\r') {
+			if (*(s+1) == '\n') {
+				*s++ = '\n';
+			} else {
+				*s = ' ';
+			}
+		}
+
+		if (iswsp(*s)) {
+			// change prior \n to spaces
+			int j;
+			for (j = 1; s - j >= buf && *(s-j) == '\n'; j++)
+				*(s-j) = ' ';
+		}
+
+		if (*s == '\n') {
+			s++;
+			if (iswsp(*s)) {
+				*(s-1) = ' ';
+			} else {			
+				*(s-1) = 0;
+				if (*(s-2) == '\n')   // ex-crlf
+					*(s-2) = 0;
+				while (s < end && *s != ':') {
+					*s = tolower(*s);
+					s++;
+				}
+			}
+		}
+	}
+
+	buf[0] = 0;
+
+/*
+	for (s = buf; s < end; ) {
+		printf("%s\n", s);
+		s += strlen(s) + 1;
+	}
+*/
+	char *v;
+	if ((v = memmem(buf, end-buf, "\0from:", 6))) {
+		printf("FROM : %s\n", v+6);
+		parse_addr(v+6, 0, 0);
+	}
+	if ((v = memmem(buf, end-buf, "\0to:", 4))) {
+		printf("TO : %s\n", v+4);
+		char *a = v+4;
+		char *disp, *addr;
+		do {
+			a = parse_addr(a, &disp, &addr);
+			printf("DISP: |%s|  ADDR: |%s|\n", disp, addr);
+		} while (*a);
+	}
+	if ((v = memmem(buf, end-buf, "\0date:", 6))) {
+		printf("DATE : %s\n", v+6);
+		time_t t = parse_date(v+6);
+		if (t != -1)
+			printf("DATE :: %s", ctime(&t));
+		else
+			fprintf(stderr, "invalid date: %s\n", v+6);
+	}
+	if ((v = memmem(buf, end-buf, "\0subject:", 9))) {
+		printf("SUBJECT : %s\n", v+9);
+	}
+	
+	free(buf);
+
+	printf("used: %d %d\n", used, end-buf);
+}
+
+int
+main(int argc, char *argv[]) {
+	char *s;
+	
+	char *line = 0;
+	size_t linelen = 0;
+	int read;
+
+	int i = 0;
+
+	if (argc == 1 || (argc == 2 && strcmp(argv[1], "-") == 0)) {
+		while ((read = getdelim(&line, &linelen, '\n', stdin)) != -1) {
+			if (line[read-1] == '\n') line[read-1] = 0;
+			fprintf(stderr, "%s\n", line);
+			blaze822(line);
+			i++;
+		}
+	} else {
+		for (i = 1; i < argc; i++) {
+			fprintf(stderr, "%s\n", argv[i]);
+			blaze822(argv[i]);
+		}
+		i--;
+	}
+
+	printf("%d mails scanned\n", i);
+
+	return 0;
+}