vcs-svn/line_buffer.c

   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
  12 int 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
  20 int 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
  28 int buffer_deinit(struct line_buffer *buf)
  29 {
  30         int err;
  31         if (buf->infile == stdin)
  32                 return ferror(buf->infile);
  33         err = ferror(buf->infile);
  34         err |= fclose(buf->infile);
  35         return err;
  36 }
  37
  38 int buffer_read_char(struct line_buffer *buf)
  39 {
  40         return fgetc(buf->infile);
  41 }
  42
  43 /* Read a line without trailing newline. */
  44 char *buffer_read_line(struct line_buffer *buf)
  45 {
  46         char *end;
  47         if (!fgets(buf->line_buffer, sizeof(buf->line_buffer), buf->infile))
  48                 /* Error or data exhausted. */
  49                 return NULL;
  50         end = buf->line_buffer + strlen(buf->line_buffer);
  51         if (end[-1] == '\n')
  52                 end[-1] = '\0';
  53         else if (feof(buf->infile))
  54                 ; /* No newline at end of file.  That's fine. */
  55         else
  56                 /*
  57                  * Line was too long.
  58                  * There is probably a saner way to deal with this,
  59                  * but for now let's return an error.
  60                  */
  61                 return NULL;
  62         return buf->line_buffer;
  63 }
  64
  65 char *buffer_read_string(struct line_buffer *buf, uint32_t len)
  66 {
  67         strbuf_reset(&buf->blob_buffer);
  68         strbuf_fread(&buf->blob_buffer, len, buf->infile);
  69         return ferror(buf->infile) ? NULL : buf->blob_buffer.buf;
  70 }
  71
  72 void buffer_read_binary(struct line_buffer *buf,
  73                                 struct strbuf *sb, uint32_t size)
  74 {
  75         strbuf_fread(sb, size, buf->infile);
  76 }
  77
  78 void buffer_copy_bytes(struct line_buffer *buf, uint32_t len)
  79 {
  80         char byte_buffer[COPY_BUFFER_LEN];
  81         uint32_t in;
  82         while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
  83                 in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
  84                 in = fread(byte_buffer, 1, in, buf->infile);
  85                 len -= in;
  86                 fwrite(byte_buffer, 1, in, stdout);
  87                 if (ferror(stdout)) {
  88                         buffer_skip_bytes(buf, len);
  89                         return;
  90                 }
  91         }
  92 }
  93
  94 void buffer_skip_bytes(struct line_buffer *buf, uint32_t len)
  95 {
  96         char byte_buffer[COPY_BUFFER_LEN];
  97         uint32_t in;
  98         while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
  99                 in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
 100                 in = fread(byte_buffer, 1, in, buf->infile);
 101                 len -= in;
 102         }
 103 }
 104
 105 void buffer_reset(struct line_buffer *buf)
 106 {
 107         strbuf_release(&buf->blob_buffer);
 108 }