path: root/gemini.patch

From: Rene Kita <mail@rkta.de>
Subject: Add Gemini support

This patch adds Gemini support to w3m. This is still work in progress. Consider
this as alpha stage. INPUT may break with unquoted chars.

The patch should apply to the current master branch of
https://github.com/tats/w3m (commit c8223fed7cc631ad85d8e5665e509e7988bedbab)
also to the releases w3m-0.5.3+git20210102, w3m-0.5.3-git20220429 and
w3m-0.5.3+git20230121.
---
 buffer.c               |    9 +
 display.c              |    3 
 doc-de/README.func     |    1 
 doc/README.func        |    1 
 file.c                 |  292 ++++++++++++++++++++++++++++++++++++++++++++++++-
 html.h                 |    1 
 istream.c              |  140 ++++++++++++++++++-----
 istream.h              |    5 
 main.c                 |  152 +++++++++++++++++++++++++
 proto.h                |    1 
 rc.c                   |    5 
 rc.h                   |    2 
 scripts/w3mhelp.cgi.in |    5 
 url.c                  |   35 +++++
 14 files changed, 613 insertions(+), 39 deletions(-)

--- a/file.c
+++ b/file.c
@@ -30,6 +30,8 @@
 
 #define MAX_INPUT_SIZE 80 /* TODO - max should be screen line length */
 
+Buffer * loadGeminiBuffer(URLFile *uf, Buffer *volatile newBuf);
+
 static int frame_source = 0;
 static int need_number = 0;
 
@@ -248,7 +250,7 @@ loadSomething(URLFile *f,
        )
 	buf->type = "text/html";
     else
-	buf->type = "text/plain";
+	buf->type = buf->type ? buf->type : "text/plain";
     return buf;
 }
 
@@ -1702,7 +1704,7 @@ loadGeneralFile(char *path, ParsedURL *v
     URLFile f, *volatile of = NULL;
     ParsedURL pu;
     Buffer *b = NULL;
-    Buffer *(*volatile proc)(URLFile *, Buffer *) = loadBuffer;
+    Buffer *(*volatile proc)(URLFile *, Buffer *);
     char *volatile tpath;
     char *volatile t = "text/plain", *p, *volatile real_type = NULL;
     Buffer *volatile t_buf = NULL;
@@ -2054,6 +2056,166 @@ loadGeneralFile(char *path, ParsedURL *v
     else if (pu.scheme == SCM_DATA) {
 	t = f.guess_type;
     }
+    else if (pu.scheme == SCM_GEMINI) {
+	Str err, hdr, meta;
+	char *m;
+	long status;
+
+	if (fmInitialized) {
+	    term_cbreak();
+	    message(Sprintf("%s contacted. Waiting for reply...", pu.host)->
+		    ptr, 0, 0);
+	    refresh();
+	}
+
+	hdr = StrmyUFgets(&f);
+	if (!hdr || !hdr->length) {
+	    err = Sprintf("Could not read from %s", pu.host);
+	    goto fail;
+	}
+
+	/* Gemini response header: <STATUS><SPACE><META><CR><LF> */
+	status = strtol(hdr->ptr, &m, 10);
+	if (!IS_SPACE(*m)
+		|| hdr->length > 1024 + 2
+		|| hdr->ptr[hdr->length - 2] != '\r'
+		|| hdr->ptr[hdr->length - 1] != '\n') {
+	    Strchop(hdr);
+	    err = Sprintf("Invalid Gemini response header: %s", hdr->ptr);
+	    goto fail;
+	}
+
+	Strchop(hdr);
+	SKIP_BLANKS(m);
+	meta = Strnew_charp(m);
+
+	t_buf = newBuffer(INIT_BUFFER_WIDTH);
+	t_buf->document_header = newTextList();
+
+	charset = WC_CES_UTF_8;
+	switch(status) {
+	case 10: /* INPUT */
+	case 11: /* SENSITIVE INPUT */
+	    /* TODO(rkta): Fix quoting */
+	    term_raw();
+	    p = inputLine(Strnew_m_charp(meta->ptr, ": ", NULL)->ptr, NULL,
+			  status == 11 ? IN_PASSWORD : IN_STRING);
+	    if (!p || !*p)
+		return NULL;
+	    tpath = url_encode(Strnew_m_charp(tpath, "?", p, NULL)->ptr, NULL, 0);
+	    request = NULL;
+	    UFclose(&f);
+	    current = New(ParsedURL);
+	    copyParsedURL(current, &pu);
+	    goto load_doc;
+	case 20: /* SUCCESS */
+	    /*
+	     * Gemini spec section 3.3:
+	     * If <META> is an empty string, the MIME type MUST default to
+	     * "text/gemini; charset=utf-8".
+	     */
+	    if (!*meta->ptr) {
+		t = "text/gemini";
+		pushText(t_buf->document_header, hdr->ptr);
+		break;
+	    }
+
+	    t = m = meta->ptr;
+	    while (*m && !IS_SPACE(*m) && *m != ';') m++;
+	    if (*m)
+		*m++ = '\0';
+	    SKIP_BLANKS(m);
+
+	    while (*m) { /* Not done parsing */
+		if (!strncmp(m, "lang=", 5)) {
+		    /* Ignore this */
+		    while (*m && *m++ != ';');
+		    SKIP_BLANKS(m);
+		}
+		else if (!strncmp(m, "charset=", 8)) {
+		    m += 8;
+		    charset = wc_charset_to_ces(m);
+		    if (!charset) {
+			err = Sprintf("Unknown charset: %s", hdr->ptr);
+			goto fail;
+		    }
+		    while (*m && *m++ != ';');
+		    SKIP_BLANKS(m);
+		}
+		else {
+		    err = Sprintf("Can't parser Gemini response header: %s", hdr->ptr);
+		    goto fail;
+		}
+	    }
+
+	    t_buf->buffername = parsedURL2Str(&pu)->ptr;
+	    t_buf->document_charset = charset;
+	    t_buf->type = t;
+	    pushText(t_buf->document_header, hdr->ptr);
+	    break;
+	case 30: /* REDIRECT - TEMPORARY */
+	case 31: /* REDIRECT - PERMANENT */
+	    p = meta->ptr;
+	    if (*p == '.' || *p == '/' || !strchr(p, ':')) /* relative URI */
+		p = Strnew_m_charp("gemini://", pu.host, "/", meta->ptr,
+				   NULL)->ptr;
+	    tpath = url_encode(p, NULL, 0);
+	    request = NULL;
+	    UFclose(&f);
+	    current = New(ParsedURL);
+	    copyParsedURL(current, &pu);
+	    t_buf = newBuffer(INIT_BUFFER_WIDTH);
+	    t_buf->bufferprop |= BP_REDIRECTED;
+	    status = HTST_NORMAL;
+	    goto load_doc;
+	case 40: /* TEMPORARY FAILURE */
+	    err = Sprintf("TEMPORARY FAILURE: %s", hdr->ptr);
+	    goto fail;
+	case 41: /* SERVER UNAVAILABLE */
+	    err = Sprintf("SERVER UNAVAILABLE: %s", hdr->ptr);
+	    goto fail;
+	case 42: /* CGI ERROR */
+	    err = Sprintf("CGI ERROR: %s", hdr->ptr);
+	    goto fail;
+	case 43: /* PROXY ERROR */
+	    err = Sprintf("PROXY ERROR: %s", hdr->ptr);
+	    goto fail;
+	case 44: /* SLOW DOWN */
+	    err = Sprintf("Status code %d not implemented", status);
+	    goto fail;
+	case 50: /* PERMANENT FAILURE */
+	    err = Sprintf("PERMANENT FAILURE: %s", hdr->ptr);
+	    goto fail;
+	case 51: /* NOT FOUND */
+	    err = Sprintf("NOT FOUND: %s", hdr->ptr);
+	    goto fail;
+	case 52: /* GONE */
+	    err = Sprintf("GONE: %s", hdr->ptr);
+	    goto fail;
+	case 53: /* PROXY REQUEST REFUSED */
+	    err = Sprintf("PROXY REQUEST REFUSED: %s", hdr->ptr);
+	    goto fail;
+	case 59: /* BAD REQUEST */
+	    err = Sprintf("BAD REQUEST: %s", hdr->ptr);
+	    goto fail;
+	case 60: /* CLIENT CERTIFICATE REQUIRED */
+	    err = Sprintf("CLIENT CERTIFICATE REQUIRED: %s", hdr->ptr);
+	    goto fail;
+	case 61: /* CERTIFICATE NOT AUTHORISED */
+	    err = Sprintf("CERTIFICATE NOT AUTHORISED: %s", hdr->ptr);
+	    goto fail;
+	case 62: /* CERTIFICATE NOT VALID */
+	    err = Sprintf("CERTIFICATE NOT VALID: %s", hdr->ptr);
+	    goto fail;
+	default:
+	    err = Sprintf("Unknown status code %d", status);
+fail:
+	    TRAP_OFF;
+	    disp_err_message(err->ptr, FALSE);
+	    UFclose(&f);
+	    return NULL;
+	}
+    }
     else if (searchHeader) {
 	searchHeader = SearchHeader = FALSE;
 	if (t_buf == NULL)
@@ -2232,6 +2394,8 @@ loadGeneralFile(char *path, ParsedURL *v
 
     if (is_html_type(t))
 	proc = loadHTMLBuffer;
+    else if (!strcmp(t, "text/gemini"))
+	proc = loadGeminiBuffer;
     else if (is_plain_text_type(t))
 	proc = loadBuffer;
 #ifdef USE_IMAGE
@@ -2486,7 +2650,6 @@ is_boundary(unsigned char *ch1, unsigned
     return 1;
 }
 
-
 static void
 set_breakpoint(struct readbuffer *obuf, int tag_length)
 {
@@ -7643,6 +7806,129 @@ loadGopherSearch0(URLFile *uf, ParsedURL
 }
 #endif				/* USE_GOPHER */
 
+Buffer *
+loadGeminiBuffer(URLFile *uf, Buffer *volatile buf)
+{
+    Anchor *a;
+    FILE *src = NULL;
+    wc_ces charset;
+    Str l, line, tmpf;
+    char *spacer, *p, *q;
+    int hseq, len, nlines, pre = 0;
+    clen_t linelen = 0, trbyte = 0;
+    Lineprop *propBuf = NULL;
+    MySignalHandler(*volatile prevtrap) (SIGNAL_ARG) = NULL;
+
+    if (SETJMP(AbortLoading) != 0) {
+	goto _end;
+    }
+    TRAP_ON;
+
+    charset = buf->document_charset;
+    hseq = nlines = 0;
+    if (buf->sourcefile == NULL &&
+	(uf->scheme != SCM_LOCAL || buf->mailcap)) {
+	tmpf = tmpfname(TMPF_SRC, NULL);
+	if (!(src = fopen(tmpf->ptr, "w"))) {
+	    TRAP_OFF;
+	    disp_err_message(Sprintf("Cannot open %s, aborting!", tmpf->ptr)->ptr,
+			     FALSE);
+	    return NULL;
+	}
+	buf->sourcefile = tmpf->ptr;
+    }
+
+    while ((line = StrmyISgets(uf->stream)) && line->length) {
+	if (src)
+	    Strfputs(line, src);
+	linelen += line->length;
+	line = convertLine(uf, line, PAGER_MODE, &charset, charset);
+	Strchop(line);
+
+	p = line->ptr;
+	if (!strncmp(p, "```", 3)) {
+	    pre = !pre;
+	    continue;
+	}
+
+	++nlines;
+	showProgress(&linelen, &trbyte);
+
+	if (pre) {
+	    line = checkType(line, &propBuf, NULL);
+	    addnewline(buf, line->ptr, propBuf, NULL,
+		       line->length, FOLD_BUFFER_WIDTH, nlines);
+	    continue;
+	}
+
+	if (!strncmp(p, "=>", 2)) {
+	    p += 2;
+	    SKIP_BLANKS(p);
+	    q = p;
+	    while(*q && !IS_SPACE(*q)) q++;
+	    if (*q)
+		*q++ = '\0';
+	    SKIP_BLANKS(q);
+	    if (!*q)
+		q = p;
+	    buf->href = putAnchor(buf->href,
+				  url_encode(p, baseURL(buf), charset),
+				  NULL, &a, NO_REFERER, q, '\0', nlines, 0);
+	    buf->hmarklist = putHmarker(buf->hmarklist, currentLn(buf),
+					0, hseq);
+	    if (displayLinkNumber)
+		line = Sprintf("[%d]: %s", hseq + 1, q);
+	    else
+		line = Sprintf("%s", q);
+	    line = checkType(line, &propBuf, NULL);
+	    for (int i = 0; i < line->length; i++)
+		propBuf[i] |= PE_ANCHOR;
+	    a->end.line = nlines;
+	    a->end.pos = line->length;
+	    a->hseq = hseq++;
+	    addnewline(buf, line->ptr, propBuf, NULL,
+		       line->length, FOLD_BUFFER_WIDTH, nlines);
+	    continue;
+	}
+
+	len = line->length;
+	spacer = "";
+	if (*p == '>') {
+	    spacer = "    ";
+	    p++;
+	    SKIP_BLANKS(p);
+	}
+	while (len > buf->width) {
+	    q = &p[buf->width - (strlen(spacer) + 1)];
+	    while(!IS_SPACE(*q) && q != p) q--;
+	    if (q == p)
+		break;
+	    *q = '\0';
+	    l = checkType(Strnew_m_charp(spacer, p, NULL), &propBuf, NULL);
+	    addnewline(buf, l->ptr, propBuf, NULL, l->length, -1, nlines);
+	    nlines++;
+	    len -= (l->length - strlen(spacer));
+	    if (line->ptr[0] == '*')
+		spacer = "  ";
+	    p = q + 1;
+	}
+	l = checkType(Strnew_m_charp(spacer, p, NULL), &propBuf, NULL);
+	addnewline(buf, l->ptr, propBuf, NULL, l->length, FOLD_BUFFER_WIDTH,
+		   nlines);
+    }
+  _end:
+    TRAP_OFF;
+    if (src)
+	fclose(src);
+    UFclose(uf);
+    buf->topLine = buf->firstLine;
+    buf->lastLine = buf->currentLine;
+    buf->currentLine = buf->firstLine;
+    buf->trbyte = trbyte + linelen;
+
+    return buf;
+}
+
 /* 
  * loadBuffer: read file and make new buffer
  */
--- a/html.h
+++ b/html.h
@@ -419,5 +419,6 @@ struct environment {
 #ifdef USE_SSL
 #define SCM_HTTPS       13
 #endif				/* USE_SSL */
+#define SCM_GEMINI	14
 
 #endif				/* _HTML_H */
--- a/url.c
+++ b/url.c
@@ -75,6 +75,7 @@ static int
 #ifdef USE_SSL
     443,			/* https */
 #endif				/* USE_SSL */
+    1965			/* gemini */
 };
 
 struct cmdtable schemetable[] = {
@@ -95,6 +96,7 @@ struct cmdtable schemetable[] = {
 #ifdef USE_SSL
     {"https", SCM_HTTPS},
 #endif				/* USE_SSL */
+    {"gemini", SCM_GEMINI},
     {NULL, SCM_UNKNOWN},
 };
 
@@ -235,6 +237,7 @@ DefaultFile(int scheme)
     case SCM_LOCAL_CGI:
     case SCM_FTP:
     case SCM_FTPDIR:
+    case SCM_GEMINI:
 	return allocStr("/", -1);
     }
     return NULL;
@@ -256,7 +259,7 @@ free_ssl_ctx(void)
     if (ssl_ctx != NULL)
 	SSL_CTX_free(ssl_ctx);
     ssl_ctx = NULL;
-    ssl_accept_this_site(NULL);
+    ssl_accept_this_site(NULL, NULL, 0);
 }
 
 #if SSLEAY_VERSION_NUMBER >= 0x00905100
@@ -1262,6 +1265,7 @@ _parsedURL2Str(ParsedURL *pu, int pass,
 	"news", "news", "data", "mailto",
 #ifdef USE_SSL
 	"https",
+	"gemini",
 #endif				/* USE_SSL */
     };
 
@@ -1962,6 +1966,35 @@ openURL(char *url, ParsedURL *pu, Parsed
 	}
 	break;
 #endif				/* USE_GOPHER */
+    case SCM_GEMINI:
+	sock = openSocket(pu->host, schemeNumToName(pu->scheme), pu->port);
+	if (sock < 0) {
+	    *status = HTST_MISSING;
+	    return uf;
+	}
+	if (!(sslh = openSSLHandle(sock, pu->host,
+				   &uf.ssl_certificate))) {
+	    *status = HTST_MISSING;
+	    return uf;
+	}
+	hr->flag |= HR_FLAG_LOCAL;
+	tmp = Strnew_m_charp("gemini://", pu->host, pu->file,
+			     pu->query ?
+				     Strnew_m_charp("?", pu ->query, NULL)->ptr :
+				     "",
+			     "\r\n", NULL);
+	*status = HTST_NORMAL;
+	uf.stream = newSSLStream(sslh, sock);
+	SSL_write(sslh, tmp->ptr, tmp->length);
+	if(w3m_reqlog){
+	    FILE *ff = fopen(w3m_reqlog, "a");
+	    if (ff == NULL)
+		return uf;
+	    fputs("GEMINI: request via SSL\n", ff);
+	    fwrite(tmp->ptr, sizeof(char), tmp->length, ff);
+	    fclose(ff);
+	}
+	return uf;
 #ifdef USE_NNTP
     case SCM_NNTP:
     case SCM_NNTP_GROUP:
--- a/display.c
+++ b/display.c
@@ -382,7 +382,8 @@ displayBuffer(Buffer *buf, int mode)
     if (buf->height == 0)
 	buf->height = LASTLINE + 1;
     if ((buf->width != INIT_BUFFER_WIDTH &&
-	 (is_html_type(buf->type) || FoldLine))
+	 (is_html_type(buf->type) || FoldLine || !strcmp(buf->type,
+							 "text/gemini")))
 	|| buf->need_reshape) {
 	buf->need_reshape = TRUE;
 	reshapeBuffer(buf);
--- a/buffer.c
+++ b/buffer.c
@@ -18,6 +18,10 @@ extern int do_getch();
 char *NullLine = "";
 Lineprop NullProp[] = { 0 };
 
+
+/* TODO(rkta): header file */
+Buffer * loadGeminiBuffer(URLFile *uf, Buffer *volatile buf);
+
 /* 
  * Buffer creation
  */
@@ -507,6 +511,8 @@ reshapeBuffer(Buffer *buf)
 {
     URLFile f;
     Buffer sbuf;
+    /* TODO(rkta): Shouldn't we do this for all schemes? */
+    Str t;
 #ifdef USE_M17N
     wc_uint8 old_auto_detect = WcOption.auto_detect;
 #endif
@@ -517,6 +523,7 @@ reshapeBuffer(Buffer *buf)
     buf->width = INIT_BUFFER_WIDTH;
     if (buf->sourcefile == NULL)
 	return;
+    t = Strnew_charp(buf->type);
     init_stream(&f, SCM_LOCAL, NULL);
     examineFile(buf->mailcap_source ? buf->mailcap_source : buf->sourcefile,
 		&f);
@@ -562,6 +569,8 @@ reshapeBuffer(Buffer *buf)
 #endif
     if (is_html_type(buf->type))
 	loadHTMLBuffer(&f, buf);
+    else if (!strcmp(t->ptr, "text/gemini"))
+	loadGeminiBuffer(&f, buf);
     else
 	loadBuffer(&f, buf);
     UFclose(&f);
--- a/main.c
+++ b/main.c
@@ -406,6 +406,32 @@ die_oom(size_t bytes)
     return NULL;
 }
 
+/* TODO(rkta): header */
+TextList * load_known_hosts(void);
+
+TextList *
+load_known_hosts(void)
+{
+    FILE *f;
+    Str l;
+    TextList *kh;
+
+    kh = newTextList();
+
+    if (!(f = fopen(known_hosts_file, "r")))
+	return kh;
+
+    while (!feof(f)) {
+	l = Strfgets(f);
+	if (!l->length)
+	    continue;
+	Strchop(l);
+	pushText(kh, l->ptr);
+    }
+    fclose(f);
+    return kh;
+}
+
 int
 main(int argc, char **argv)
 {
@@ -908,6 +934,9 @@ main(int argc, char **argv)
     if (UseHistory)
 	loadHistory(URLHist);
 #endif				/* not USE_HISTORY */
+    known_hosts_file = rcFile("known_hosts");
+    if (ssl_known_hosts)
+	known_hosts = load_known_hosts();
 
 #ifdef USE_M17N
     /*  if (w3m_dump)
@@ -2557,10 +2586,36 @@ DEFUN(movRW, NEXT_WORD, "Move to the nex
     displayBuffer(Currentbuf, B_NORMAL);
 }
 
+static int
+save_known_hosts(void)
+{
+    FILE *fp;
+    TextListItem *host;
+    char *khf, *tmpf;
+
+    if (!known_hosts)
+	return 0;
+
+    tmpf = tmpfname(TMPF_HIST, NULL)->ptr;
+    khf = rcFile("known_hosts");
+    if (!(fp = fopen(tmpf, "w")))
+	return 1;
+
+    for (host = known_hosts->first; host; host = host->next)
+	fprintf(fp, "%s\n", host->ptr);
+
+    fclose(fp);
+    if (rename(tmpf, khf))
+	return 1;
+
+    return 0;
+}
+
 static void
 _quitfm(int confirm)
 {
     char *ans = "y";
+    int err = 0;
 
     if (checkDownloadList())
 	/* FIXME: gettextize? */
@@ -2587,7 +2642,9 @@ _quitfm(int confirm)
     if (UseHistory && SaveURLHist)
 	saveHistory(URLHist, URLHistSize);
 #endif				/* USE_HISTORY */
-    w3m_exit(0);
+    if ((err = save_known_hosts()))
+	perror(NULL);
+    w3m_exit(err);
 }
 
 /* Quit */
@@ -4786,6 +4843,13 @@ DEFUN(vwSrc, SOURCE VIEW, "Toggle betwee
 	displayBuffer(Currentbuf, B_NORMAL);
 	return;
     }
+
+    /* TODO(rkta): keep && document this */
+    if (!strcmp(Currentbuf->type, "text/gemini")) {
+	geminize();
+	return;
+    }
+
     if (Currentbuf->sourcefile == NULL) {
 	if (Currentbuf->pagerSource &&
 	    !strcasecmp(Currentbuf->type, "text/plain")) {
@@ -4864,6 +4928,91 @@ DEFUN(vwSrc, SOURCE VIEW, "Toggle betwee
     displayBuffer(Currentbuf, B_NORMAL);
 }
 
+DEFUN(geminize, GEMINIZE, "Toggle between text/gemini shown or processed")
+{
+    Buffer *buf;
+
+    if (Currentbuf->type == NULL || Currentbuf->bufferprop & BP_FRAME)
+	return;
+    if ((buf = Currentbuf->linkBuffer[LB_SOURCE]) != NULL ||
+	(buf = Currentbuf->linkBuffer[LB_N_SOURCE]) != NULL) {
+	Currentbuf = buf;
+	displayBuffer(Currentbuf, B_NORMAL);
+	return;
+    }
+
+    if (Currentbuf->sourcefile == NULL) {
+	if (Currentbuf->pagerSource &&
+	    !strcasecmp(Currentbuf->type, "text/plain")) {
+#ifdef USE_M17N
+	    wc_ces old_charset;
+	    wc_bool old_fix_width_conv;
+#endif
+	    FILE *f;
+	    Str tmpf = tmpfname(TMPF_SRC, NULL);
+	    f = fopen(tmpf->ptr, "w");
+	    if (f == NULL)
+		return;
+#ifdef USE_M17N
+	    old_charset = DisplayCharset;
+	    old_fix_width_conv = WcOption.fix_width_conv;
+	    DisplayCharset = (Currentbuf->document_charset != WC_CES_US_ASCII)
+		? Currentbuf->document_charset : 0;
+	    WcOption.fix_width_conv = WC_FALSE;
+#endif
+	    saveBufferBody(Currentbuf, f, TRUE);
+#ifdef USE_M17N
+	    DisplayCharset = old_charset;
+	    WcOption.fix_width_conv = old_fix_width_conv;
+#endif
+	    fclose(f);
+	    Currentbuf->sourcefile = tmpf->ptr;
+	}
+	else {
+	    return;
+	}
+    }
+
+    buf = newBuffer(INIT_BUFFER_WIDTH);
+
+    if (!strcmp(Currentbuf->type, "text/gemini")) {
+	buf->type = "text/plain";
+	buf->real_type = Currentbuf->real_type;
+	buf->buffername = Sprintf("source of %s", Currentbuf->buffername)->ptr;
+	buf->linkBuffer[LB_N_SOURCE] = Currentbuf;
+	Currentbuf->linkBuffer[LB_SOURCE] = buf;
+    }
+    else if (!strcasecmp(Currentbuf->type, "text/plain")) {
+	buf->type = "text/gemini";
+	if (Currentbuf->real_type &&
+	    !strcasecmp(Currentbuf->real_type, "text/plain"))
+	    buf->real_type = "text/gemini";
+	else
+	    buf->real_type = Currentbuf->real_type;
+	buf->buffername = Sprintf("Gemini view of %s",
+				  Currentbuf->buffername)->ptr;
+	buf->linkBuffer[LB_SOURCE] = Currentbuf;
+	Currentbuf->linkBuffer[LB_N_SOURCE] = buf;
+    }
+    else {
+	return;
+    }
+    buf->currentURL = Currentbuf->currentURL;
+    buf->real_scheme = Currentbuf->real_scheme;
+    buf->filename = Currentbuf->filename;
+    buf->sourcefile = Currentbuf->sourcefile;
+    buf->header_source = Currentbuf->header_source;
+    buf->search_header = Currentbuf->search_header;
+    buf->document_charset = Currentbuf->document_charset;
+    buf->clone = Currentbuf->clone;
+    (*buf->clone)++;
+
+    buf->need_reshape = TRUE;
+    reshapeBuffer(buf);
+    pushBuffer(buf);
+    displayBuffer(Currentbuf, B_NORMAL);
+}
+
 /* reload */
 DEFUN(reload, RELOAD, "Load current document anew")
 {
@@ -5089,6 +5238,7 @@ chkURLBuffer(Buffer *buf)
 	"https?://[a-zA-Z0-9:%\\-\\./_@]*\\[[a-fA-F0-9:][a-fA-F0-9:\\.]*\\][a-zA-Z0-9:%\\-\\./?=~_\\&+@#,\\$;]*",
 	"ftp://[a-zA-Z0-9:%\\-\\./_@]*\\[[a-fA-F0-9:][a-fA-F0-9:\\.]*\\][a-zA-Z0-9:%\\-\\./=_+@#,\\$]*",
 #endif				/* INET6 */
+	"gemini:/[a-zA-Z0-9:%\\-\\./=_\\+@#,\\$;]*",
 	NULL
     };
     int i;
--- a/proto.h
+++ b/proto.h
@@ -97,6 +97,7 @@ extern void peekURL(void);
 extern void peekIMG(void);
 extern void curURL(void);
 extern void vwSrc(void);
+extern void geminize(void);
 extern void reload(void);
 extern void reshape(void);
 extern void chkURL(void);
--- a/istream.c
+++ b/istream.c
@@ -1,6 +1,7 @@
 /* $Id: istream.c,v 1.27 2010/07/18 13:43:23 htrb Exp $ */
 #include "fm.h"
 #include "myctype.h"
+#include "rc.h"
 #include "istream.h"
 #include <signal.h>
 #ifdef USE_SSL
@@ -350,15 +351,43 @@ ISeos(InputStream stream)
 }
 
 #ifdef USE_SSL
-static Str accept_this_site;
+TextList *known_hosts;
+char *known_hosts_file;
+static Str _accept_this_site;
+
+static Str
+X509_fingerprint(X509 *x)
+{
+    Str fp = Strnew();
+    const EVP_MD *digest;
+    unsigned n;
+    unsigned char md[EVP_MAX_MD_SIZE];
+
+    digest = EVP_get_digestbyname("sha1");
+    X509_digest(x, digest, md, &n);
+    for(int i = 0; i < n - 1; i++)
+	Strcat(fp, Sprintf("%02x:", md[i]));
+    Strcat(fp, Sprintf("%02x", md[n - 1]));
+
+    return fp;
+}
 
 void
-ssl_accept_this_site(char *hostname)
+ssl_accept_this_site(char *hostname, X509 *x, int perm)
 {
-    if (hostname)
-	accept_this_site = Strnew_charp(hostname);
-    else
-	accept_this_site = NULL;
+
+    if (!hostname)
+	return;
+
+    if (!perm) {
+	_accept_this_site = Strnew_charp(hostname);
+    }
+    else {
+	pushText(known_hosts, Strnew_m_charp(hostname,
+					     " ",
+					     X509_fingerprint(x)->ptr,
+					     NULL)->ptr);
+    }
 }
 
 static int
@@ -497,6 +526,50 @@ ssl_check_cert_ident(X509 * x, char *hos
     return ret;
 }
 
+/* TODO(rkta): header */
+TextList * load_known_hosts(void);
+
+/* Return true if the host's cert was manually accepted before */
+static int
+accept_this_site(const char *hostname, X509 *x)
+{
+    Str fp;
+    TextListItem *host;
+    char *h;
+    size_t n;
+
+    if (!ssl_known_hosts) {
+	if (!_accept_this_site)
+	    return 0;
+	return !strncasecmp(_accept_this_site->ptr,
+			    hostname,
+			    _accept_this_site->length);
+    }
+
+    if (!known_hosts && (!(known_hosts = load_known_hosts())))
+	known_hosts = newTextList();
+
+    if (!(host = known_hosts->last)) /* Empty list */
+	return 0;
+
+    n = strlen(hostname);
+    fp = X509_fingerprint(x);
+    if (!strncasecmp(host->ptr, hostname, n)
+	&& !strncmp(host->ptr + n + 1, fp->ptr, fp->length))
+	return 1;
+
+    for (host = host->prev; host; host = host->prev) {
+	if (!strncasecmp(host->ptr, hostname, n)
+	    && !strncmp(host->ptr + n + 1, fp->ptr, fp->length)) {
+	    h = host->ptr;
+	    delText(known_hosts, host);
+	    pushText(known_hosts, h);
+	    return 1;
+	}
+    }
+    return 0;
+}
+
 Str
 ssl_get_certificate(SSL * ssl, char *hostname)
 {
@@ -504,7 +577,7 @@ ssl_get_certificate(SSL * ssl, char *hos
     X509 *x;
     X509_NAME *xn;
     char *p;
-    int len;
+    int len, perm;
     Str s;
     char buf[2048];
     Str amsg = NULL;
@@ -513,10 +586,10 @@ ssl_get_certificate(SSL * ssl, char *hos
 
     if (ssl == NULL)
 	return NULL;
+
     x = SSL_get_peer_certificate(ssl);
     if (x == NULL) {
-	if (accept_this_site
-	    && strcasecmp(accept_this_site->ptr, hostname) == 0)
+	if (accept_this_site(hostname, x))
 	    ans = "y";
 	else {
 	    /* FIXME: gettextize? */
@@ -537,7 +610,7 @@ ssl_get_certificate(SSL * ssl, char *hos
 	}
 	if (amsg)
 	    disp_err_message(amsg->ptr, FALSE);
-	ssl_accept_this_site(hostname);
+	ssl_accept_this_site(hostname, x, 0);
 	/* FIXME: gettextize? */
 	s = amsg ? amsg : Strnew_charp("valid certificate");
 	return s;
@@ -547,39 +620,46 @@ ssl_get_certificate(SSL * ssl, char *hos
      * The chain length is automatically checked by OpenSSL when we
      * set the verify depth in the ctx.
      */
+    perm = 0;
     if (ssl_verify_server) {
 	long verr;
 	if ((verr = SSL_get_verify_result(ssl))
 	    != X509_V_OK) {
 	    const char *em = X509_verify_cert_error_string(verr);
-	    if (accept_this_site
-		&& strcasecmp(accept_this_site->ptr, hostname) == 0)
+	    if (accept_this_site(hostname, x))
 		ans = "y";
 	    else {
-		/* FIXME: gettextize? */
-		emsg = Sprintf("%s: accept? (y/n)", em);
+		if (ssl_known_hosts)
+		    emsg = Sprintf("%s: accept? (y)es/(n)o/(a)lways)", em);
+		else
+		    emsg = Sprintf("%s: accept? (y/n)", em);
 		ans = inputAnswer(emsg->ptr);
-	    }
-	    if (ans && TOLOWER(*ans) == 'y') {
-		/* FIXME: gettextize? */
-		amsg = Sprintf("Accept unsecure SSL session: "
-			       "unverified: %s", em);
-	    }
-	    else {
-		/* FIXME: gettextize? */
-		char *e =
-		    Sprintf("This SSL session was rejected: %s", em)->ptr;
-		disp_err_message(e, FALSE);
-		free_ssl_ctx();
-		return NULL;
+		if (ans && TOLOWER(*ans) == 'y') {
+		    /* FIXME: gettextize? */
+		    amsg = Sprintf("Accept unsecure SSL session: "
+				   "unverified: %s", em);
+		}
+		else if (ssl_known_hosts && ans && TOLOWER(*ans) == 'a') {
+		    amsg = Sprintf("Permanently accepted unverified SSL"
+				   "session: %s", em);
+		    perm = 1;
+		}
+		else {
+		    /* FIXME: gettextize? */
+		    char *e =
+			Sprintf("This SSL session was rejected: %s", em)->ptr;
+		    disp_err_message(e, FALSE);
+		    free_ssl_ctx();
+		    return NULL;
+		}
 	    }
 	}
+	ssl_accept_this_site(hostname, x, perm);
     }
 #endif
     emsg = ssl_check_cert_ident(x, hostname);
     if (emsg != NULL) {
-	if (accept_this_site
-	    && strcasecmp(accept_this_site->ptr, hostname) == 0)
+	if (accept_this_site(hostname, x))
 	    ans = "y";
 	else {
 	    Str ep = Strdup(emsg);
@@ -601,10 +681,10 @@ ssl_get_certificate(SSL * ssl, char *hos
 	    free_ssl_ctx();
 	    return NULL;
 	}
+	ssl_accept_this_site(hostname, x, 0);
     }
     if (amsg)
 	disp_err_message(amsg->ptr, FALSE);
-    ssl_accept_this_site(hostname);
     /* FIXME: gettextize? */
     s = amsg ? amsg : Strnew_charp("valid certificate");
     Strcat_charp(s, "\n");
--- a/istream.h
+++ b/istream.h
@@ -109,6 +109,9 @@ typedef struct encoded_stream *EncodedSt
 
 typedef union input_stream *InputStream;
 
+extern TextList *known_hosts;
+extern char *known_hosts_file;
+
 extern InputStream newInputStream(int des);
 extern InputStream newFileStream(FILE * f, void (*closep) ());
 extern InputStream newStrStream(Str s);
@@ -130,7 +133,7 @@ int ISread_n(InputStream stream, char *d
 extern int ISfileno(InputStream stream);
 extern int ISeos(InputStream stream);
 #ifdef USE_SSL
-extern void ssl_accept_this_site(char *hostname);
+extern void ssl_accept_this_site(char *hostname, X509 *x, int perm);
 extern Str ssl_get_certificate(SSL * ssl, char *hostname);
 #endif
 
--- a/rc.c
+++ b/rc.c
@@ -36,6 +36,8 @@ struct rc_search_table {
 static struct rc_search_table *RC_search_table;
 static int RC_table_size;
 
+int ssl_known_hosts = 1;
+
 #define P_INT      0
 #define P_SHORT    1
 #define P_CHARINT  2
@@ -209,6 +211,7 @@ static int OptionEncode = FALSE;
 #define CMT_SSL_CA_PATH N_("Path to directory for PEM encoded certificates of CAs")
 #define CMT_SSL_CA_FILE N_("File consisting of PEM encoded certificates of CAs")
 #define CMT_SSL_CA_DEFAULT N_("Use default locations for PEM encoded certificates of CAs")
+#define CMT_SSL_KNOWN_HOSTS N_("Remember accepted self signed certificates")
 #endif				/* USE_SSL_VERIFY */
 #define CMT_SSL_FORBID_METHOD N_("List of forbidden SSL methods (2: SSLv2, 3: SSLv3, t: TLSv1.0, 5: TLSv1.1, 6: TLSv1.2, 7: TLSv1.3)")
 #ifdef SSL_CTX_set_min_proto_version
@@ -647,6 +650,8 @@ struct param_ptr params7[] = {
      NULL},
     {"ssl_ca_default", P_INT, PI_ONOFF, (void *)&ssl_ca_default,
      CMT_SSL_CA_DEFAULT, NULL},
+    {"ssl_known_hosts", P_INT, PI_ONOFF, (void *)&ssl_known_hosts,
+     CMT_SSL_KNOWN_HOSTS, NULL},
 #endif				/* USE_SSL_VERIFY */
     {NULL, 0, 0, NULL, NULL, NULL},
 };
--- a/rc.h
+++ b/rc.h
@@ -4,4 +4,6 @@
 extern void show_params(FILE * fp);
 extern int str_to_bool(char *value, int old);
 
+extern int ssl_known_hosts;
+
 #endif /* RC_H */
--- a/doc-de/README.func
+++ b/doc-de/README.func
@@ -32,6 +32,7 @@ EXIT		Sofort beenden
 EXTERN		Verwende externen Browser zur Anzeige
 EXTERN_LINK	Verwende externen Browser zur Anzeige des Linkziels
 FRAME		Wechsle zwischen Kennung und Umsetzung von HTML-Frames
+GEMINIZE	Wechsle zwischen text/gemini-Wiedergabe und -Verarbeitung
 GOTO		Öffne angegebenes Dokument in neuem Puffer
 GOTO_HOME	Zurück zur Startseite (die Variablen HTTP_HOME oder WWW_HOME spezifiziert wurden)
 GOTO_LINE	Gehe zur angebenen Zeile
--- a/doc/README.func
+++ b/doc/README.func
@@ -32,6 +32,7 @@ EXIT		Quit without confirmation
 EXTERN		Display using an external browser
 EXTERN_LINK	Display target using an external browser
 FRAME		Toggle rendering HTML frames
+GEMINIZE	Toggle between text/gemini shown or processed
 GOTO		Open specified document in a new buffer
 GOTO_HOME	Return to the homepage (specified HTTP_HOME or WWW_HOME variable)
 GOTO_LINE	Go to the specified line
--- a/scripts/w3mhelp.cgi.in
+++ b/scripts/w3mhelp.cgi.in
@@ -152,8 +152,9 @@ print "<P><A HREF=\"$keymap\">$head</A>\
 		pipeBuf"));
 
 &show_keymap('Buffer Operations',
-	     split(" ", "backBf nextBf prevBf goHome selMn selBuf vwSrc svSrc
-		svBuf editBf editScr reload reshape rdrwSc dispI stopI"));
+	     split(" ", "backBf nextBf prevBf goHome selMn selBuf geminize
+		vwSrc svSrc svBuf editBf editScr reload reshape rdrwSc
+		dispI stopI"));
 
 &show_keymap('Tab Operations',
 	     split(" ", "newT closeT nextT prevT tabMn tabR tabL"));