From 90c0a3cfe390208c86144bf97ec8fa5610febe0f Mon Sep 17 00:00:00 2001 From: David Barr Date: Mon, 13 Dec 2010 19:56:01 +1100 Subject: [PATCH] vcs-svn: implement perfect hash for top-level keys Instead of interning property names and comparing their string_pool keys, look them up in a table by string length, which should be about as fast. Another small step towards removing dependence on string_pool altogether. Signed-off-by: David Barr Signed-off-by: Jonathan Nieder --- vcs-svn/svndump.c | 109 +++++++++++++++++++++++++--------------------- 1 file changed, 59 insertions(+), 50 deletions(-) diff --git a/vcs-svn/svndump.c b/vcs-svn/svndump.c index 322d1cd30..77680a31e 100644 --- a/vcs-svn/svndump.c +++ b/vcs-svn/svndump.c @@ -63,14 +63,6 @@ static struct { uint32_t version, uuid, url; } dump_ctx; -static struct { - uint32_t uuid, revision_number, node_path, node_kind, node_action, - node_copyfrom_path, node_copyfrom_rev, text_content_length, - prop_content_length, content_length, svn_fs_dump_format_version, - /* version 3 format */ - text_delta, prop_delta; -} keys; - static void reset_node_ctx(char *fname) { node_ctx.type = 0; @@ -99,24 +91,6 @@ static void reset_dump_ctx(uint32_t url) dump_ctx.uuid = ~0; } -static void init_keys(void) -{ - keys.uuid = pool_intern("UUID"); - keys.revision_number = pool_intern("Revision-number"); - keys.node_path = pool_intern("Node-path"); - keys.node_kind = pool_intern("Node-kind"); - keys.node_action = pool_intern("Node-action"); - keys.node_copyfrom_path = pool_intern("Node-copyfrom-path"); - keys.node_copyfrom_rev = pool_intern("Node-copyfrom-rev"); - keys.text_content_length = pool_intern("Text-content-length"); - keys.prop_content_length = pool_intern("Prop-content-length"); - keys.content_length = pool_intern("Content-length"); - keys.svn_fs_dump_format_version = pool_intern("SVN-fs-dump-format-version"); - /* version 3 format (Subversion 1.1.0) */ - keys.text_delta = pool_intern("Text-delta"); - keys.prop_delta = pool_intern("Prop-delta"); -} - static void handle_property(const struct strbuf *key_buf, const char *val, uint32_t len, uint32_t *type_set) @@ -320,44 +294,61 @@ void svndump_read(const char *url) char *t; uint32_t active_ctx = DUMP_CTX; uint32_t len; - uint32_t key; reset_dump_ctx(pool_intern(url)); while ((t = buffer_read_line(&input))) { val = strstr(t, ": "); if (!val) continue; - *val++ = '\0'; - *val++ = '\0'; - key = pool_intern(t); + val += 2; - if (key == keys.svn_fs_dump_format_version) { + /* strlen(key) + 1 */ + switch (val - t - 1) { + case sizeof("SVN-fs-dump-format-version"): + if (constcmp(t, "SVN-fs-dump-format-version")) + continue; dump_ctx.version = atoi(val); if (dump_ctx.version > 3) die("expected svn dump format version <= 3, found %"PRIu32, dump_ctx.version); - } else if (key == keys.uuid) { + break; + case sizeof("UUID"): + if (constcmp(t, "UUID")) + continue; dump_ctx.uuid = pool_intern(val); - } else if (key == keys.revision_number) { + break; + case sizeof("Revision-number"): + if (constcmp(t, "Revision-number")) + continue; if (active_ctx == NODE_CTX) handle_node(); if (active_ctx != DUMP_CTX) handle_revision(); active_ctx = REV_CTX; reset_rev_ctx(atoi(val)); - } else if (key == keys.node_path) { - if (active_ctx == NODE_CTX) - handle_node(); - active_ctx = NODE_CTX; - reset_node_ctx(val); - } else if (key == keys.node_kind) { + break; + case sizeof("Node-path"): + if (prefixcmp(t, "Node-")) + continue; + if (!constcmp(t + strlen("Node-"), "path")) { + if (active_ctx == NODE_CTX) + handle_node(); + active_ctx = NODE_CTX; + reset_node_ctx(val); + break; + } + if (constcmp(t + strlen("Node-"), "kind")) + continue; if (!strcmp(val, "dir")) node_ctx.type = REPO_MODE_DIR; else if (!strcmp(val, "file")) node_ctx.type = REPO_MODE_BLB; else fprintf(stderr, "Unknown node-kind: %s\n", val); - } else if (key == keys.node_action) { + break; + case sizeof("Node-action"): + if (constcmp(t, "Node-action")) + continue; if (!strcmp(val, "delete")) { node_ctx.action = NODEACT_DELETE; } else if (!strcmp(val, "add")) { @@ -370,19 +361,38 @@ void svndump_read(const char *url) fprintf(stderr, "Unknown node-action: %s\n", val); node_ctx.action = NODEACT_UNKNOWN; } - } else if (key == keys.node_copyfrom_path) { + break; + case sizeof("Node-copyfrom-path"): + if (constcmp(t, "Node-copyfrom-path")) + continue; pool_tok_seq(REPO_MAX_PATH_DEPTH, node_ctx.src, "/", val); - } else if (key == keys.node_copyfrom_rev) { + break; + case sizeof("Node-copyfrom-rev"): + if (constcmp(t, "Node-copyfrom-rev")) + continue; node_ctx.srcRev = atoi(val); - } else if (key == keys.text_content_length) { - node_ctx.textLength = atoi(val); - } else if (key == keys.prop_content_length) { + break; + case sizeof("Text-content-length"): + if (!constcmp(t, "Text-content-length")) { + node_ctx.textLength = atoi(val); + break; + } + if (constcmp(t, "Prop-content-length")) + continue; node_ctx.propLength = atoi(val); - } else if (key == keys.text_delta) { - node_ctx.text_delta = !strcmp(val, "true"); - } else if (key == keys.prop_delta) { + break; + case sizeof("Text-delta"): + if (!constcmp(t, "Text-delta")) { + node_ctx.text_delta = !strcmp(val, "true"); + break; + } + if (constcmp(t, "Prop-delta")) + continue; node_ctx.prop_delta = !strcmp(val, "true"); - } else if (key == keys.content_length) { + break; + case sizeof("Content-length"): + if (constcmp(t, "Content-length")) + continue; len = atoi(val); t = buffer_read_line(&input); if (!t) @@ -417,7 +427,6 @@ int svndump_init(const char *filename) reset_dump_ctx(~0); reset_rev_ctx(0); reset_node_ctx(NULL); - init_keys(); return 0; } -- 2.26.2