Add seprintf
Based on seprint(2) from Plan 9. I'm not sure if my return value exactly matches Plan 9's in the case of truncation. seprint(2) is described only as returning a pointer to the terminating '\0', but if it does so even in the case of truncation, it is awkward for the caller to detect. This implementation returns end in the truncation case, so that (ptr == end) indicates truncation.master
parent
3d931d0f5a
commit
5c3cd59af6
12
chat.h
12
chat.h
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@ -44,6 +44,18 @@
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typedef unsigned uint;
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typedef unsigned uint;
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typedef unsigned char byte;
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typedef unsigned char byte;
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static inline char *seprintf(char *ptr, char *end, const char *fmt, ...)
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__attribute__((format(printf, 3, 4)));
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static inline char *seprintf(char *ptr, char *end, const char *fmt, ...) {
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va_list ap;
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va_start(ap, fmt);
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int n = vsnprintf(ptr, end - ptr, fmt, ap);
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va_end(ap);
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if (n < 0) return NULL;
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ptr += n;
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return (ptr > end ? end : ptr);
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}
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struct Cat {
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struct Cat {
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char *buf;
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char *buf;
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size_t cap;
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size_t cap;
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