Mercurial > hg
diff mercurial/cext/revlog.c @ 48722:92b5a2c4d637
revlog: split revlog v1 and revlog v2 handling
Explicitly splitting their fields packing and unpacking makes it easier to
extend the existing C implemenation to handle the new changelog format, whose
fields and offsets are not simply a superset of the revlog.
Differential Revision: https://phab.mercurial-scm.org/D12137
author | pacien <pacien.trangirard@pacien.net> |
---|---|
date | Wed, 26 Jan 2022 13:18:48 +0100 |
parents | a9364de9be29 |
children | d9a7131648a3 |
line wrap: on
line diff
--- a/mercurial/cext/revlog.c Wed Jan 26 13:08:36 2022 +0100 +++ b/mercurial/cext/revlog.c Wed Jan 26 13:18:48 2022 +0100 @@ -136,19 +136,29 @@ static const long format_v1 = 1; /* Internal only, could be any number */ static const long format_v2 = 2; /* Internal only, could be any number */ -static const long entry_offset_high = 0; -static const long entry_offset_offset_flags = 4; -static const long entry_offset_comp_len = 8; -static const long entry_offset_uncomp_len = 12; -static const long entry_offset_base_rev = 16; -static const long entry_offset_link_rev = 20; -static const long entry_offset_parent_1 = 24; -static const long entry_offset_parent_2 = 28; -static const long entry_offset_node_id = 32; -static const long entry_offset_sidedata_offset = 64; -static const long entry_offset_sidedata_comp_len = 72; -static const long entry_offset_all_comp_mode = 76; -static const long entry_offset_padding_start = 77; +static const long entry_v1_offset_high = 0; +static const long entry_v1_offset_offset_flags = 4; +static const long entry_v1_offset_comp_len = 8; +static const long entry_v1_offset_uncomp_len = 12; +static const long entry_v1_offset_base_rev = 16; +static const long entry_v1_offset_link_rev = 20; +static const long entry_v1_offset_parent_1 = 24; +static const long entry_v1_offset_parent_2 = 28; +static const long entry_v1_offset_node_id = 32; + +static const long entry_v2_offset_high = 0; +static const long entry_v2_offset_offset_flags = 4; +static const long entry_v2_offset_comp_len = 8; +static const long entry_v2_offset_uncomp_len = 12; +static const long entry_v2_offset_base_rev = 16; +static const long entry_v2_offset_link_rev = 20; +static const long entry_v2_offset_parent_1 = 24; +static const long entry_v2_offset_parent_2 = 28; +static const long entry_v2_offset_node_id = 32; +static const long entry_v2_offset_sidedata_offset = 64; +static const long entry_v2_offset_sidedata_comp_len = 72; +static const long entry_v2_offset_all_comp_mode = 76; +static const long entry_v2_offset_padding_start = 77; static const char comp_mode_inline = 2; static const char rank_unknown = -1; @@ -220,8 +230,16 @@ { const char *data = index_deref(self, rev); - ps[0] = getbe32(data + entry_offset_parent_1); - ps[1] = getbe32(data + entry_offset_parent_2); + if (self->format_version == format_v1) { + ps[0] = getbe32(data + entry_v1_offset_parent_1); + ps[1] = getbe32(data + entry_v1_offset_parent_2); + } else if (self->format_version == format_v2) { + ps[0] = getbe32(data + entry_v2_offset_parent_1); + ps[1] = getbe32(data + entry_v2_offset_parent_2); + } else { + raise_revlog_error(); + return -1; + } /* If index file is corrupted, ps[] may point to invalid revisions. So * there is a risk of buffer overflow to trust them unconditionally. */ @@ -268,14 +286,32 @@ return 0; data = index_deref(self, rev); - offset = getbe32(data + entry_offset_offset_flags); - if (rev == 0) { - /* mask out version number for the first entry */ - offset &= 0xFFFF; + + if (self->format_version == format_v1) { + offset = getbe32(data + entry_v1_offset_offset_flags); + if (rev == 0) { + /* mask out version number for the first entry */ + offset &= 0xFFFF; + } else { + uint32_t offset_high = + getbe32(data + entry_v1_offset_high); + offset |= ((uint64_t)offset_high) << 32; + } + } else if (self->format_version == format_v2) { + offset = getbe32(data + entry_v2_offset_offset_flags); + if (rev == 0) { + /* mask out version number for the first entry */ + offset &= 0xFFFF; + } else { + uint32_t offset_high = + getbe32(data + entry_v2_offset_high); + offset |= ((uint64_t)offset_high) << 32; + } } else { - uint32_t offset_high = getbe32(data + entry_offset_high); - offset |= ((uint64_t)offset_high) << 32; + raise_revlog_error(); + return -1; } + return (int64_t)(offset >> 16); } @@ -289,7 +325,14 @@ data = index_deref(self, rev); - tmp = (int)getbe32(data + entry_offset_comp_len); + if (self->format_version == format_v1) { + tmp = (int)getbe32(data + entry_v1_offset_comp_len); + } else if (self->format_version == format_v2) { + tmp = (int)getbe32(data + entry_v2_offset_comp_len); + } else { + raise_revlog_error(); + return -1; + } if (tmp < 0) { PyErr_Format(PyExc_OverflowError, "revlog entry size out of bound (%d)", tmp); @@ -334,38 +377,66 @@ if (data == NULL) return NULL; - offset_flags = getbe32(data + entry_offset_offset_flags); - /* - * The first entry on-disk needs the version number masked out, - * but this doesn't apply if entries are added to an empty index. - */ - if (self->length && pos == 0) - offset_flags &= 0xFFFF; - else { - uint32_t offset_high = getbe32(data + entry_offset_high); - offset_flags |= ((uint64_t)offset_high) << 32; - } - - comp_len = getbe32(data + entry_offset_comp_len); - uncomp_len = getbe32(data + entry_offset_uncomp_len); - base_rev = getbe32(data + entry_offset_base_rev); - link_rev = getbe32(data + entry_offset_link_rev); - parent_1 = getbe32(data + entry_offset_parent_1); - parent_2 = getbe32(data + entry_offset_parent_2); - c_node_id = data + entry_offset_node_id; - if (self->format_version == format_v1) { + offset_flags = getbe32(data + entry_v1_offset_offset_flags); + /* + * The first entry on-disk needs the version number masked out, + * but this doesn't apply if entries are added to an empty + * index. + */ + if (self->length && pos == 0) + offset_flags &= 0xFFFF; + else { + uint32_t offset_high = + getbe32(data + entry_v1_offset_high); + offset_flags |= ((uint64_t)offset_high) << 32; + } + + comp_len = getbe32(data + entry_v1_offset_comp_len); + uncomp_len = getbe32(data + entry_v1_offset_uncomp_len); + base_rev = getbe32(data + entry_v1_offset_base_rev); + link_rev = getbe32(data + entry_v1_offset_link_rev); + parent_1 = getbe32(data + entry_v1_offset_parent_1); + parent_2 = getbe32(data + entry_v1_offset_parent_2); + c_node_id = data + entry_v1_offset_node_id; + sidedata_offset = 0; sidedata_comp_len = 0; data_comp_mode = comp_mode_inline; sidedata_comp_mode = comp_mode_inline; - } else { - sidedata_offset = getbe64(data + entry_offset_sidedata_offset); + } else if (self->format_version == format_v2) { + offset_flags = getbe32(data + entry_v2_offset_offset_flags); + /* + * The first entry on-disk needs the version number masked out, + * but this doesn't apply if entries are added to an empty + * index. + */ + if (self->length && pos == 0) + offset_flags &= 0xFFFF; + else { + uint32_t offset_high = + getbe32(data + entry_v2_offset_high); + offset_flags |= ((uint64_t)offset_high) << 32; + } + + comp_len = getbe32(data + entry_v2_offset_comp_len); + uncomp_len = getbe32(data + entry_v2_offset_uncomp_len); + base_rev = getbe32(data + entry_v2_offset_base_rev); + link_rev = getbe32(data + entry_v2_offset_link_rev); + parent_1 = getbe32(data + entry_v2_offset_parent_1); + parent_2 = getbe32(data + entry_v2_offset_parent_2); + c_node_id = data + entry_v2_offset_node_id; + + sidedata_offset = + getbe64(data + entry_v2_offset_sidedata_offset); sidedata_comp_len = - getbe32(data + entry_offset_sidedata_comp_len); - data_comp_mode = data[entry_offset_all_comp_mode] & 3; + getbe32(data + entry_v2_offset_sidedata_comp_len); + data_comp_mode = data[entry_v2_offset_all_comp_mode] & 3; sidedata_comp_mode = - ((data[entry_offset_all_comp_mode] >> 2) & 3); + ((data[entry_v2_offset_all_comp_mode] >> 2) & 3); + } else { + raise_revlog_error(); + return NULL; } return Py_BuildValue(tuple_format, offset_flags, comp_len, uncomp_len, @@ -429,6 +500,7 @@ { Py_ssize_t length = index_length(self); const char *data; + const char *node_id; if (pos == nullrev) return nullid; @@ -437,7 +509,17 @@ return NULL; data = index_deref(self, pos); - return data ? data + entry_offset_node_id : NULL; + + if (self->format_version == format_v1) { + node_id = data + entry_v1_offset_node_id; + } else if (self->format_version == format_v2) { + node_id = data + entry_v2_offset_node_id; + } else { + raise_revlog_error(); + return NULL; + } + + return data ? node_id : NULL; } /* @@ -520,28 +602,50 @@ } rev = self->length + self->new_length; data = self->added + self->entry_size * self->new_length++; - putbe32(offset_flags >> 32, data + entry_offset_high); - putbe32(offset_flags & 0xffffffffU, data + entry_offset_offset_flags); - putbe32(comp_len, data + entry_offset_comp_len); - putbe32(uncomp_len, data + entry_offset_uncomp_len); - putbe32(base_rev, data + entry_offset_base_rev); - putbe32(link_rev, data + entry_offset_link_rev); - putbe32(parent_1, data + entry_offset_parent_1); - putbe32(parent_2, data + entry_offset_parent_2); - memcpy(data + entry_offset_node_id, c_node_id, c_node_id_len); - /* Padding since SHA-1 is only 20 bytes for now */ - memset(data + entry_offset_node_id + c_node_id_len, 0, - entry_offset_node_id - c_node_id_len); - if (self->format_version == format_v2) { - putbe64(sidedata_offset, data + entry_offset_sidedata_offset); + + if (self->format_version == format_v1) { + putbe32(offset_flags >> 32, data + entry_v1_offset_high); + putbe32(offset_flags & 0xffffffffU, + data + entry_v1_offset_offset_flags); + putbe32(comp_len, data + entry_v1_offset_comp_len); + putbe32(uncomp_len, data + entry_v1_offset_uncomp_len); + putbe32(base_rev, data + entry_v1_offset_base_rev); + putbe32(link_rev, data + entry_v1_offset_link_rev); + putbe32(parent_1, data + entry_v1_offset_parent_1); + putbe32(parent_2, data + entry_v1_offset_parent_2); + memcpy(data + entry_v1_offset_node_id, c_node_id, + c_node_id_len); + /* Padding since SHA-1 is only 20 bytes for now */ + memset(data + entry_v1_offset_node_id + c_node_id_len, 0, + entry_v1_offset_node_id - c_node_id_len); + } else if (self->format_version == format_v2) { + putbe32(offset_flags >> 32, data + entry_v2_offset_high); + putbe32(offset_flags & 0xffffffffU, + data + entry_v2_offset_offset_flags); + putbe32(comp_len, data + entry_v2_offset_comp_len); + putbe32(uncomp_len, data + entry_v2_offset_uncomp_len); + putbe32(base_rev, data + entry_v2_offset_base_rev); + putbe32(link_rev, data + entry_v2_offset_link_rev); + putbe32(parent_1, data + entry_v2_offset_parent_1); + putbe32(parent_2, data + entry_v2_offset_parent_2); + memcpy(data + entry_v2_offset_node_id, c_node_id, + c_node_id_len); + /* Padding since SHA-1 is only 20 bytes for now */ + memset(data + entry_v2_offset_node_id + c_node_id_len, 0, + entry_v2_offset_node_id - c_node_id_len); + putbe64(sidedata_offset, + data + entry_v2_offset_sidedata_offset); putbe32(sidedata_comp_len, - data + entry_offset_sidedata_comp_len); + data + entry_v2_offset_sidedata_comp_len); comp_field = data_comp_mode & 3; comp_field = comp_field | (sidedata_comp_mode & 3) << 2; - data[entry_offset_all_comp_mode] = comp_field; + data[entry_v2_offset_all_comp_mode] = comp_field; /* Padding for 96 bytes alignment */ - memset(data + entry_offset_padding_start, 0, - self->entry_size - entry_offset_padding_start); + memset(data + entry_v2_offset_padding_start, 0, + self->entry_size - entry_v2_offset_padding_start); + } else { + raise_revlog_error(); + return NULL; } if (self->ntinitialized) @@ -596,11 +700,11 @@ /* Find the newly added node, offset from the "already on-disk" length */ data = self->added + self->entry_size * (rev - self->length); - putbe64(offset_flags, data + entry_offset_high); - putbe64(sidedata_offset, data + entry_offset_sidedata_offset); - putbe32(sidedata_comp_len, data + entry_offset_sidedata_comp_len); - data[entry_offset_all_comp_mode] = - (data[entry_offset_all_comp_mode] & ~(3 << 2)) | + putbe64(offset_flags, data + entry_v2_offset_high); + putbe64(sidedata_offset, data + entry_v2_offset_sidedata_offset); + putbe32(sidedata_comp_len, data + entry_v2_offset_sidedata_comp_len); + data[entry_v2_offset_all_comp_mode] = + (data[entry_v2_offset_all_comp_mode] & ~(3 << 2)) | ((comp_mode & 3) << 2); Py_RETURN_NONE; @@ -1144,7 +1248,15 @@ data = index_deref(self, rev); if (data == NULL) return -2; - result = getbe32(data + entry_offset_base_rev); + + if (self->format_version == format_v1) { + result = getbe32(data + entry_v1_offset_base_rev); + } else if (self->format_version == format_v2) { + result = getbe32(data + entry_v2_offset_base_rev); + } else { + raise_revlog_error(); + return -1; + } if (result > rev) { PyErr_Format( @@ -2756,10 +2868,18 @@ while (pos + self->entry_size <= end && pos >= 0) { uint32_t comp_len, sidedata_comp_len = 0; /* 3rd element of header is length of compressed inline data */ - comp_len = getbe32(data + pos + entry_offset_comp_len); - if (self->entry_size == v2_entry_size) { + if (self->format_version == format_v1) { + comp_len = + getbe32(data + pos + entry_v1_offset_comp_len); + sidedata_comp_len = 0; + } else if (self->format_version == format_v2) { + comp_len = + getbe32(data + pos + entry_v2_offset_comp_len); sidedata_comp_len = getbe32( - data + pos + entry_offset_sidedata_comp_len); + data + pos + entry_v2_offset_sidedata_comp_len); + } else { + raise_revlog_error(); + return -1; } incr = self->entry_size + comp_len + sidedata_comp_len; if (offsets)