Andrew's git - gitweb.git/blob - vcs-svn/line

   1/*
   2 * Licensed under a two-clause BSD-style license.
   3 * See LICENSE for details.
   4 */
   5
   6#include "git-compat-util.h"
   7#include "line_buffer.h"
   8#include "strbuf.h"
   9
  10#define COPY_BUFFER_LEN 4096
  11
  12int buffer_init(struct line_buffer *buf, const char *filename)
  13{
  14        buf->infile = filename ? fopen(filename, "r") : stdin;
  15        if (!buf->infile)
  16                return -1;
  17        return 0;
  18}
  19
  20int buffer_fdinit(struct line_buffer *buf, int fd)
  21{
  22        buf->infile = fdopen(fd, "r");
  23        if (!buf->infile)
  24                return -1;
  25        return 0;
  26}
  27
  28int buffer_tmpfile_init(struct line_buffer *buf)
  29{
  30        buf->infile = tmpfile();
  31        if (!buf->infile)
  32                return -1;
  33        return 0;
  34}
  35
  36int buffer_deinit(struct line_buffer *buf)
  37{
  38        int err;
  39        if (buf->infile == stdin)
  40                return ferror(buf->infile);
  41        err = ferror(buf->infile);
  42        err |= fclose(buf->infile);
  43        return err;
  44}
  45
  46FILE *buffer_tmpfile_rewind(struct line_buffer *buf)
  47{
  48        rewind(buf->infile);
  49        return buf->infile;
  50}
  51
  52long buffer_tmpfile_prepare_to_read(struct line_buffer *buf)
  53{
  54        long pos = ftell(buf->infile);
  55        if (pos < 0)
  56                return error_errno("ftell error");
  57        if (fseek(buf->infile, 0, SEEK_SET))
  58                return error_errno("seek error");
  59        return pos;
  60}
  61
  62int buffer_ferror(struct line_buffer *buf)
  63{
  64        return ferror(buf->infile);
  65}
  66
  67int buffer_read_char(struct line_buffer *buf)
  68{
  69        return fgetc(buf->infile);
  70}
  71
  72/* Read a line without trailing newline. */
  73char *buffer_read_line(struct line_buffer *buf)
  74{
  75        char *end;
  76        if (!fgets(buf->line_buffer, sizeof(buf->line_buffer), buf->infile))
  77                /* Error or data exhausted. */
  78                return NULL;
  79        end = buf->line_buffer + strlen(buf->line_buffer);
  80        if (end[-1] == '\n')
  81                end[-1] = '\0';
  82        else if (feof(buf->infile))
  83                ; /* No newline at end of file.  That's fine. */
  84        else
  85                /*
  86                 * Line was too long.
  87                 * There is probably a saner way to deal with this,
  88                 * but for now let's return an error.
  89                 */
  90                return NULL;
  91        return buf->line_buffer;
  92}
  93
  94size_t buffer_read_binary(struct line_buffer *buf,
  95                                struct strbuf *sb, size_t size)
  96{
  97        return strbuf_fread(sb, size, buf->infile);
  98}
  99
 100off_t buffer_copy_bytes(struct line_buffer *buf, off_t nbytes)
 101{
 102        char byte_buffer[COPY_BUFFER_LEN];
 103        off_t done = 0;
 104        while (done < nbytes && !feof(buf->infile) && !ferror(buf->infile)) {
 105                off_t len = nbytes - done;
 106                size_t in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
 107                in = fread(byte_buffer, 1, in, buf->infile);
 108                done += in;
 109                fwrite(byte_buffer, 1, in, stdout);
 110                if (ferror(stdout))
 111                        return done + buffer_skip_bytes(buf, nbytes - done);
 112        }
 113        return done;
 114}
 115
 116off_t buffer_skip_bytes(struct line_buffer *buf, off_t nbytes)
 117{
 118        char byte_buffer[COPY_BUFFER_LEN];
 119        off_t done = 0;
 120        while (done < nbytes && !feof(buf->infile) && !ferror(buf->infile)) {
 121                off_t len = nbytes - done;
 122                size_t in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
 123                done += fread(byte_buffer, 1, in, buf->infile);
 124        }
 125        return done;
 126}