From b5c82a91a5a136ccdd7c1dc16ba2b616a0099f7c Mon Sep 17 00:00:00 2001
From: mbays <mbays@sdf.org>
Date: Sat, 22 Jul 2023 00:00:00 +0000
Subject: [PATCH] munge links to handle following links from an old state

---
 main.c | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/main.c b/main.c
index e2c293a..822bf24 100644
--- a/main.c
+++ b/main.c
@@ -34,6 +34,7 @@ typedef struct Child {
     int out;
     int flag;
     bool reading;
+    int serial;
 
     bool nolink;
     bool plain;
@@ -149,12 +150,14 @@ static void set_child_last_active(Child *child)
 static int stream_text(int in, int flag, int out,
         bool escape_pre,
         bool escape_all,
+        int munge_links_serial,
         bool *child_reading,
         int read_timeout, int pause_timeout) {
     char buf[256];
     struct pollfd pfd[2] = { { in, POLLIN | POLLHUP, 0 }, {flag, POLLIN, 0 } };
     int backticks = 0;
     char escape = 0;
+    int munge = 0;
     bool read_something = false;
 
     /* Note we set no total maximum time or output size limit; we leave it to 
@@ -184,7 +187,22 @@ static int stream_text(int in, int flag, int out,
                     } else while (--backticks >= 0) write(out, "`", 1);
                 }
 
-                if (escape_all && escape > 0) {
+                if (munge_links_serial > 0) {
+                    // Replace "=>[whitespace]?foo" at start of a line with
+                    // "=>[whitespace?!l+[serial]?foo"
+                    if ((munge == 0 && *b == '=') ||
+                        (munge == 1 && *b == '>') ||
+                        (munge == 2 && (*b == ' ' || *b == '\t'))) {
+                        munge++;
+                    } else if (munge == 3 && (*b == '?')) {
+                        dprintf(out, "?!l+%d", munge_links_serial);
+                        munge = -1;
+                    } else if (*b == '\n') {
+                        munge = 0;
+                    } else {
+                        munge = -1;
+                    }
+                } else if (escape_all && escape > 0) {
                     if (escape == '\n') {
                         if (*b == '#' || *b == '>') {
                             write(out, " ", 1);
@@ -203,6 +221,7 @@ static int stream_text(int in, int flag, int out,
                     escape = 0;
                 }
 
+
                 write(out, b, 1);
                 ++b;
             }
@@ -449,6 +468,18 @@ static void do_command(const State* state, Child *child, const char* q, int sock
             put("Gemtext mode enabled.\n");
             put("=> ?!? Input command\n");
             return;
+        } else if (0 == strncmp(q, "l+", strlen("l+"))) {
+            q += 2;
+            if (child->serial == atoi(q)) {
+                while (*q && *q != '?') {
+                    q++;
+                }
+            } else {
+                put("20 text/gemini\r\n");
+                put("That link is stale.\n");
+                put("=> ?!? Input command\n");
+                return;
+            }
         } else if (*q != '!') {
             put("40 Unknown gemrepl meta-command (use '!!' for a literal '!')\r\n");
             return;
@@ -458,6 +489,8 @@ static void do_command(const State* state, Child *child, const char* q, int sock
         return;
     }
 
+    child->serial++;
+
     if (state->format != raw) {
         if (child->plain) put("20 text/plain\r\n");
         else put("20 text/gemini\r\n");
@@ -486,6 +519,7 @@ static void do_command(const State* state, Child *child, const char* q, int sock
     const int succ = stream_text(child->out, child->flag, socket,
             state->format == pre && !child->plain,
             state->format == unwrapped && !child->plain,
+            state->format == gemtext ? child->serial : 0,
             &child->reading,
             state->read_timeout,
             state->pause_timeout);
-- 
2.11.4.GIT