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fix poll() / getline() buffered IO desync #109

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trollkotze wants to merge 2 commits into from
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fix poll() / getline() buffered IO desync #109

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5cd2226
fix poll() / getline() buffered IO desync
trollkotze Mar 22, 2026
21e9f73
Fix file buffer check on MacOS / BSD (hopefully)
trollkotze Mar 22, 2026
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25 changes: 15 additions & 10 deletions src/mcp/mcp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -2389,16 +2389,21 @@ int cbm_mcp_server_run(cbm_mcp_server_t *srv, FILE *in, FILE *out) {
continue;
}
#else
struct pollfd pfd = {.fd = fd, .events = POLLIN};
int pr = poll(&pfd, 1, STORE_IDLE_TIMEOUT_S * 1000);

if (pr < 0) {
break; /* error or signal */
}
if (pr == 0) {
/* Timeout — evict idle store to free resources */
cbm_mcp_server_evict_idle(srv, STORE_IDLE_TIMEOUT_S);
continue;
#ifdef __GLIBC__
int has_buffered = (in->_IO_read_ptr < in->_IO_read_end);
#else
/* macOS / BSD: use __srget-style check.
* fp->_r is the count of unread bytes in the buffer. */
int has_buffered = (in->_r > 0);
#endif
if (!has_buffered) {
struct pollfd pfd = {.fd = fd, .events = POLLIN};
int pr = poll(&pfd, 1, STORE_IDLE_TIMEOUT_S * 1000);
if (pr < 0) break;
if (pr == 0) {
cbm_mcp_server_evict_idle(srv, STORE_IDLE_TIMEOUT_S);
continue;
}
}
#endif

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