commit 3aba13f77927e669d80009b2318c6d3d3d90a922 Author: Nick Mathewson nickm@torproject.org Date: Wed Sep 4 11:06:15 2019 -0400
buffers: use ptrdiff_t to indicate offsets.
Previously we used int in some places and off_t for others. Neither is correct: ptrdiff_t is right for differences between pointers. (off_t is only for offsets and sizes on the filesystem.) --- src/lib/buf/buffers.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/src/lib/buf/buffers.c b/src/lib/buf/buffers.c index 88a25b847..4d026bd37 100644 --- a/src/lib/buf/buffers.c +++ b/src/lib/buf/buffers.c @@ -158,7 +158,7 @@ chunk_new_with_alloc_size(size_t alloc) static inline chunk_t * chunk_grow(chunk_t *chunk, size_t sz) { - off_t offset; + ptrdiff_t offset; const size_t memlen_orig = chunk->memlen; const size_t orig_alloc = CHUNK_ALLOC_SIZE(memlen_orig); const size_t new_alloc = CHUNK_ALLOC_SIZE(sz); @@ -440,7 +440,7 @@ chunk_copy(const chunk_t *in_chunk) #endif newch->next = NULL; if (in_chunk->data) { - off_t offset = in_chunk->data - in_chunk->mem; + ptrdiff_t offset = in_chunk->data - in_chunk->mem; newch->data = newch->mem + offset; } return newch; @@ -710,7 +710,8 @@ buf_move_all(buf_t *buf_out, buf_t *buf_in) /** Internal structure: represents a position in a buffer. */ typedef struct buf_pos_t { const chunk_t *chunk; /**< Which chunk are we pointing to? */ - int pos;/**< Which character inside the chunk's data are we pointing to? */ + ptrdiff_t pos;/**< Which character inside the chunk's data are we pointing + * to? */ size_t chunk_pos; /**< Total length of all previous chunks. */ } buf_pos_t;
@@ -726,15 +727,15 @@ buf_pos_init(const buf_t *buf, buf_pos_t *out) /** Advance <b>out</b> to the first appearance of <b>ch</b> at the current * position of <b>out</b>, or later. Return -1 if no instances are found; * otherwise returns the absolute position of the character. */ -static off_t +static ptrdiff_t buf_find_pos_of_char(char ch, buf_pos_t *out) { const chunk_t *chunk; - int pos; + ptrdiff_t pos; tor_assert(out); if (out->chunk) { if (out->chunk->datalen) { - tor_assert(out->pos < (off_t)out->chunk->datalen); + tor_assert(out->pos < (ptrdiff_t)out->chunk->datalen); } else { tor_assert(out->pos == 0); } @@ -762,7 +763,7 @@ buf_pos_inc(buf_pos_t *pos) { tor_assert(pos->pos < INT_MAX - 1); ++pos->pos; - if (pos->pos == (off_t)pos->chunk->datalen) { + if (pos->pos == (ptrdiff_t)pos->chunk->datalen) { if (!pos->chunk->next) return -1; pos->chunk_pos += pos->chunk->datalen; @@ -836,11 +837,11 @@ buf_peek_startswith(const buf_t *buf, const char *cmd)
/** Return the index within <b>buf</b> at which <b>ch</b> first appears, * or -1 if <b>ch</b> does not appear on buf. */ -static off_t +static ptrdiff_t buf_find_offset_of_char(buf_t *buf, char ch) { chunk_t *chunk; - off_t offset = 0; + ptrdiff_t offset = 0; tor_assert(buf->datalen < INT_MAX); for (chunk = buf->head; chunk; chunk = chunk->next) { char *cp = memchr(chunk->data, ch, chunk->datalen); @@ -863,7 +864,7 @@ int buf_get_line(buf_t *buf, char *data_out, size_t *data_len) { size_t sz; - off_t offset; + ptrdiff_t offset;
if (!buf->head) return 0;