Date: Sun, 10 Oct 2010 21:41:06 -0500
Collect the line_buffer state in a newly public line_buffer struct. Callers can use multiple line_buffers to manage input from multiple files at a time.
svn-fe's delta applier will use this to stream a delta from svnrdump and the preimage it applies to from fast-import at the same time.
The tests don't take advantage of the new features, but I think that's okay. It is easier to find lingering examples of nonreentrant code by searching for "static" in line_buffer.c.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
That's it. The API change feels inevitable to me, perhaps because it
has been in use for so long. Hopefully it can be a good basis for
future changes:
- buffer_tmpfile_{init,rewind,prepare_to_read}, for when files are
just a place to stash data for later
- buffer_fdopen to read from a file descriptor
- buffer_interactive for deadlock avoidance (if that turns out to
be needed)I would be happy to hear any thoughts you have, even as basic as "looks ok" or "confusing".
thanks, Jonathan
test-line-buffer.c | 17 +++++++++--------
vcs-svn/fast_export.c | 6 +++---
vcs-svn/fast_export.h | 5 ++++-
vcs-svn/line_buffer.c | 20 ++++++++------------
vcs-svn/line_buffer.h | 14 +++++++-------
vcs-svn/line_buffer.txt | 5 +++--
vcs-svn/svndump.c | 29 ++++++++++++++++-------------
7 files changed, 50 insertions(+), 46 deletions(-)
Show changes to 7 files +50 −46
test-line-buffer.c, vcs-svn/fast_export.c, vcs-svn/fast_export.h, vcs-svn/line_buffer.c, vcs-svn/line_buffer.h, vcs-svn/line_buffer.txt, vcs-svn/svndump.c
diff --git a/test-line-buffer.c b/test-line-buffer.c
index c11bf7f..f9af892 100644
--- a/test-line-buffer.c
+++ b/test-line-buffer.c
@@ -22,25 +22,26 @@ static uint32_t strtouint32(const char *s)
int main(int argc, char *argv[])
{
+ struct line_buffer buf = LINE_BUFFER_INIT;
char *s;
if (argc != 1)
usage("test-line-buffer < input.txt");
- if (buffer_init(NULL))
+ if (buffer_init(&buf, NULL))
die_errno("open error");
- while ((s = buffer_read_line())) {
- s = buffer_read_string(strtouint32(s));
+ while ((s = buffer_read_line(&buf))) {
+ s = buffer_read_string(&buf, strtouint32(s));
fputs(s, stdout);
fputc('\n', stdout);
- buffer_skip_bytes(1);
- if (!(s = buffer_read_line()))
+ buffer_skip_bytes(&buf, 1);
+ if (!(s = buffer_read_line(&buf)))
break;
- buffer_copy_bytes(strtouint32(s) + 1);
+ buffer_copy_bytes(&buf, strtouint32(s) + 1);
}
- if (buffer_deinit())
+ if (buffer_deinit(&buf))
die("input error");
if (ferror(stdout))
die("output error");
- buffer_reset();
+ buffer_reset(&buf);
return 0;
}
diff --git a/vcs-svn/fast_export.c b/vcs-svn/fast_export.c
index 6cfa256..260cf50 100644
--- a/vcs-svn/fast_export.c
+++ b/vcs-svn/fast_export.c
@@ -63,14 +63,14 @@ void fast_export_commit(uint32_t revision, uint32_t author, char *log,
printf("progress Imported commit %"PRIu32".\n\n", revision);
}
-void fast_export_blob(uint32_t mode, uint32_t mark, uint32_t len)
+void fast_export_blob(uint32_t mode, uint32_t mark, uint32_t len, struct line_buffer *input)
{
if (mode == REPO_MODE_LNK) {
/* svn symlink blobs start with "link " */
- buffer_skip_bytes(5);
+ buffer_skip_bytes(input, 5);
len -= 5;
}
printf("blob\nmark :%"PRIu32"\ndata %"PRIu32"\n", mark, len);
- buffer_copy_bytes(len);
+ buffer_copy_bytes(input, len);
fputc('\n', stdout);
}
diff --git a/vcs-svn/fast_export.h b/vcs-svn/fast_export.h
index 2aaaea5..054e7d5 100644
--- a/vcs-svn/fast_export.h
+++ b/vcs-svn/fast_export.h
@@ -1,11 +1,14 @@
#ifndef FAST_EXPORT_H_
#define FAST_EXPORT_H_
+#include "line_buffer.h"
+
void fast_export_delete(uint32_t depth, uint32_t *path);
void fast_export_modify(uint32_t depth, uint32_t *path, uint32_t mode,
uint32_t mark);
void fast_export_commit(uint32_t revision, uint32_t author, char *log,
uint32_t uuid, uint32_t url, unsigned long timestamp);
-void fast_export_blob(uint32_t mode, uint32_t mark, uint32_t len);
+void fast_export_blob(uint32_t mode, uint32_t mark, uint32_t len,
+ struct line_buffer *input);
#endif
diff --git a/vcs-svn/line_buffer.c b/vcs-svn/line_buffer.c
index e7bc230..806932b 100644
--- a/vcs-svn/line_buffer.c
+++ b/vcs-svn/line_buffer.c
@@ -8,20 +8,16 @@
#include "strbuf.h"
#define COPY_BUFFER_LEN 4096
-static struct line_buffer buf_ = LINE_BUFFER_INIT;
-static struct line_buffer *buf;
-int buffer_init(const char *filename)
+int buffer_init(struct line_buffer *buf, const char *filename)
{
- buf = &buf_;
-
buf->infile = filename ? fopen(filename, "r") : stdin;
if (!buf->infile)
return -1;
return 0;
}
-int buffer_deinit(void)
+int buffer_deinit(struct line_buffer *buf)
{
int err;
if (buf->infile == stdin)
@@ -32,7 +28,7 @@ int buffer_deinit(void)
}
/* Read a line without trailing newline. */
-char *buffer_read_line(void)
+char *buffer_read_line(struct line_buffer *buf)
{
char *end;
if (!fgets(buf->line_buffer, sizeof(buf->line_buffer), buf->infile))
@@ -53,14 +49,14 @@ char *buffer_read_line(void)
return buf->line_buffer;
}
-char *buffer_read_string(uint32_t len)
+char *buffer_read_string(struct line_buffer *buf, uint32_t len)
{
strbuf_reset(&buf->blob_buffer);
strbuf_fread(&buf->blob_buffer, len, buf->infile);
return ferror(buf->infile) ? NULL : buf->blob_buffer.buf;
}
-void buffer_copy_bytes(uint32_t len)
+void buffer_copy_bytes(struct line_buffer *buf, uint32_t len)
{
char byte_buffer[COPY_BUFFER_LEN];
uint32_t in;
@@ -70,13 +66,13 @@ void buffer_copy_bytes(uint32_t len)
len -= in;
fwrite(byte_buffer, 1, in, stdout);
if (ferror(stdout)) {
- buffer_skip_bytes(len);
+ buffer_skip_bytes(buf, len);
return;
}
}
}
-void buffer_skip_bytes(uint32_t len)
+void buffer_skip_bytes(struct line_buffer *buf, uint32_t len)
{
char byte_buffer[COPY_BUFFER_LEN];
uint32_t in;
@@ -87,7 +83,7 @@ void buffer_skip_bytes(uint32_t len)
}
}
-void buffer_reset(void)
+void buffer_reset(struct line_buffer *buf)
{
strbuf_release(&buf->blob_buffer);
}
diff --git a/vcs-svn/line_buffer.h b/vcs-svn/line_buffer.h
index 4ae1133..fb37390 100644
--- a/vcs-svn/line_buffer.h
+++ b/vcs-svn/line_buffer.h
@@ -12,12 +12,12 @@ struct line_buffer {
};
#define LINE_BUFFER_INIT {"", STRBUF_INIT, NULL}
-int buffer_init(const char *filename);
-int buffer_deinit(void);
-char *buffer_read_line(void);
-char *buffer_read_string(uint32_t len);
-void buffer_copy_bytes(uint32_t len);
-void buffer_skip_bytes(uint32_t len);
-void buffer_reset(void);
+int buffer_init(struct line_buffer *buf, const char *filename);
+int buffer_deinit(struct line_buffer *buf);
+char *buffer_read_line(struct line_buffer *buf);
+char *buffer_read_string(struct line_buffer *buf, uint32_t len);
+void buffer_copy_bytes(struct line_buffer *buf, uint32_t len);
+void buffer_skip_bytes(struct line_buffer *buf, uint32_t len);
+void buffer_reset(struct line_buffer *buf);
#endif
diff --git a/vcs-svn/line_buffer.txt b/vcs-svn/line_buffer.txt
index 8906fb1..f8eaa4d 100644
--- a/vcs-svn/line_buffer.txt
+++ b/vcs-svn/line_buffer.txt
@@ -14,14 +14,15 @@ Calling sequence
The calling program:
+ - initializes a `struct line_buffer` to LINE_BUFFER_INIT
- specifies a file to read with `buffer_init`
- processes input with `buffer_read_line`, `buffer_read_string`,
`buffer_skip_bytes`, and `buffer_copy_bytes`
- closes the file with `buffer_deinit`, perhaps to start over and
read another file.
-Before exiting, the caller can use `buffer_reset` to deallocate
-resources for the benefit of profiling tools.
+When finished, the caller can use `buffer_reset` to deallocate
+resources.
Functions
---------
diff --git a/vcs-svn/svndump.c b/vcs-svn/svndump.c
index 53d0215..3bba0fe 100644
--- a/vcs-svn/svndump.c
+++ b/vcs-svn/svndump.c
@@ -30,6 +30,8 @@
/* Create memory pool for log messages */
obj_pool_gen(log, char, 4096)
+static struct line_buffer input = LINE_BUFFER_INIT;
+
static char* log_copy(uint32_t length, char *log)
{
char *buffer;
@@ -113,14 +115,14 @@ static void read_props(void)
uint32_t key = ~0;
char *val = NULL;
char *t;
- while ((t = buffer_read_line()) && strcmp(t, "PROPS-END")) {
+ while ((t = buffer_read_line(&input)) && strcmp(t, "PROPS-END")) {
if (!strncmp(t, "K ", 2)) {
len = atoi(&t[2]);
- key = pool_intern(buffer_read_string(len));
- buffer_read_line();
+ key = pool_intern(buffer_read_string(&input, len));
+ buffer_read_line(&input);
} else if (!strncmp(t, "V ", 2)) {
len = atoi(&t[2]);
- val = buffer_read_string(len);
+ val = buffer_read_string(&input, len);
if (key == keys.svn_log) {
/* Value length excludes terminating nul. */
rev_ctx.log = log_copy(len + 1, val);
@@ -135,7 +137,7 @@ static void read_props(void)
node_ctx.type = REPO_MODE_LNK;
}
key = ~0;
- buffer_read_line();
+ buffer_read_line(&input);
}
}
}
@@ -177,9 +179,10 @@ static void handle_node(void)
node_ctx.type = node_ctx.srcMode;
if (node_ctx.mark)
- fast_export_blob(node_ctx.type, node_ctx.mark, node_ctx.textLength);
+ fast_export_blob(node_ctx.type,
+ node_ctx.mark, node_ctx.textLength, &input);
else if (node_ctx.textLength != LENGTH_UNKNOWN)
- buffer_skip_bytes(node_ctx.textLength);
+ buffer_skip_bytes(&input, node_ctx.textLength);
}
static void handle_revision(void)
@@ -198,7 +201,7 @@ void svndump_read(const char *url)
uint32_t key;
reset_dump_ctx(pool_intern(url));
- while ((t = buffer_read_line())) {
+ while ((t = buffer_read_line(&input))) {
val = strstr(t, ": ");
if (!val)
continue;
@@ -250,7 +253,7 @@ void svndump_read(const char *url)
node_ctx.propLength = atoi(val);
} else if (key == keys.content_length) {
len = atoi(val);
- buffer_read_line();
+ buffer_read_line(&input);
if (active_ctx == REV_CTX) {
read_props();
} else if (active_ctx == NODE_CTX) {
@@ -258,7 +261,7 @@ void svndump_read(const char *url)
active_ctx = REV_CTX;
} else {
fprintf(stderr, "Unexpected content length header: %"PRIu32"\n", len);
- buffer_skip_bytes(len);
+ buffer_skip_bytes(&input, len);
}
}
}
@@ -270,7 +273,7 @@ void svndump_read(const char *url)
void svndump_init(const char *filename)
{
- buffer_init(filename);
+ buffer_init(&input, filename);
repo_init();
reset_dump_ctx(~0);
reset_rev_ctx(0);
@@ -285,7 +288,7 @@ void svndump_deinit(void)
reset_dump_ctx(~0);
reset_rev_ctx(0);
reset_node_ctx(NULL);
- if (buffer_deinit())
+ if (buffer_deinit(&input))
fprintf(stderr, "Input error\n");
if (ferror(stdout))
fprintf(stderr, "Output error\n");
@@ -294,7 +297,7 @@ void svndump_deinit(void)
void svndump_reset(void)
{
log_reset();
- buffer_reset();
+ buffer_reset(&input);
repo_reset();
reset_dump_ctx(~0);
reset_rev_ctx(0);
Jonathan Nieder
