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Diffstat (limited to 'docs')
| -rw-r--r-- | docs/DYNBUF.md | 80 | ||||
| -rw-r--r-- | docs/Makefile.am | 1 |
2 files changed, 81 insertions, 0 deletions
diff --git a/docs/DYNBUF.md b/docs/DYNBUF.md new file mode 100644 index 000000000..ff9009de3 --- /dev/null +++ b/docs/DYNBUF.md @@ -0,0 +1,80 @@ +# dynbuf + +This is the internal module for creating and handling "dynamic buffers". This +means buffers that can be appended to, dynamically and grow in size to adapt. + +There will always be a terminating zero put at the end of the dynamic buffer. + +The `struct dynbuf` is used to hold data for each instance of a dynamic +buffer. The members of that struct **MUST NOT** be accessed or modified +without using the dedicated dynbuf API. + +## init + + void Curl_dyn_init(struct dynbuf *s, size_t toobig); + +This inits a struct to use for dynbuf and it can't fail. The `toobig` value +**must** be set to the maximum size we allow this buffer instance to grow to. +The functions below will return `CURLE_OUT_OF_MEMORY` when hitting this limit. + +## free + + void Curl_dyn_free(struct dynbuf *s); + +Free the associated memory and clean up. After a free, the `dynbuf` struct can +be re-used to start appending new data to. + +## addn + + CURLcode Curl_dyn_addn(struct dynbuf *s, const void *mem, size_t len); + +Append arbitrary data of a given length to the end of the buffer. + +## add + + CURLcode Curl_dyn_add(struct dynbuf *s, const char *str); + +Append a C string to the end of the buffer. + +## addf + + CURLcode Curl_dyn_addf(struct dynbuf *s, const char *fmt, ...); + +Append a `printf()`-style string to the end of the buffer. + +## reset + + void Curl_dyn_reset(struct dynbuf *s); + +Reset the buffer length, but leave the allocation. + +## tail + + CURLcode Curl_dyn_trail(struct dynbuf *s, size_t length) + +Keep `length` bytes of the buffer tail (the last `length` bytes of the +buffer). The rest of the buffer is dropped. The specified `length` must not be +larger than the buffer length. (**This function is currently not provided**.) + +## ptr + + char *Curl_dyn_ptr(const struct dynbuf *s); + +Returns a `char *` to the buffer. Since the buffer may be reallocated, this +pointer should not be trusted or used anymore after the next buffer +manipulation call. + +## uptr + + unsigned char *Curl_dyn_uptr(const struct dynbuf *s); + +Returns an `unsigned char *` to the buffer. Since the buffer may be +reallocated, this pointer should not be trusted or used anymore after the next +buffer manipulation call. + +## len + + size_t Curl_dyn_len(const struct dynbuf *s); + +Returns the length of the buffer in bytes. Does not include the terminating +zero byte. diff --git a/docs/Makefile.am b/docs/Makefile.am index 860be45f2..51bcf16c6 100644 --- a/docs/Makefile.am +++ b/docs/Makefile.am @@ -54,6 +54,7 @@ EXTRA_DIST = \ CONTRIBUTE.md \ CURL-DISABLE.md \ DEPRECATE.md \ + DYNBUF.md \ ESNI.md \ EXPERIMENTAL.md \ FAQ \ |