Prevent spaceAvailable from possibly going negative

PaulZC · PaulZC · commit 54f397a2bde4 · 2025-08-28T09:34:56.000+01:00
diff --git a/Firmware/RTK_Everywhere/Tasks.ino b/Firmware/RTK_Everywhere/Tasks.ino
@@ -835,7 +835,8 @@ void processUart1Message(SEMP_PARSE_STATE *parse, uint16_t type)
             if (appleAccessory->latestEASessionDataIsBlocking() == false)
             {
                 size_t spaceAvailable = latestEASessionDataMaxLen - strlen(latestEASessionData);
-                spaceAvailable -= 3; // Leave room for the CR, LF and NULL
+                if (spaceAvailable >= 3)
+                    spaceAvailable -= 3; // Leave room for the CR, LF and NULL
                 while (spaceAvailable < parse->length) // If the buffer is full, delete the oldest message(s)
                 {
                     const char *lfPtr = strstr(latestEASessionData, "\n"); // Find the first LF

Original file line number	Diff line number	Diff line change
`@@ -835,7 +835,8 @@ void processUart1Message(SEMP_PARSE_STATE *parse, uint16_t type)`
`835`	`835`	`if (appleAccessory->latestEASessionDataIsBlocking() == false)`
`836`	`836`	`{`
`837`	`837`	`size_t spaceAvailable = latestEASessionDataMaxLen - strlen(latestEASessionData);`
`838`		`- spaceAvailable -= 3; // Leave room for the CR, LF and NULL`
	`838`	`+ if (spaceAvailable >= 3)`
	`839`	`+ spaceAvailable -= 3; // Leave room for the CR, LF and NULL`
`839`	`840`	`while (spaceAvailable < parse->length) // If the buffer is full, delete the oldest message(s)`
`840`	`841`	`{`
`841`	`842`	`const char *lfPtr = strstr(latestEASessionData, "\n"); // Find the first LF`