concat: Use plain read/write instead of buffered stdio
If we are just copying data from one file to another, we don't need to fill a complete buffer, just read a chunk at a time, and write it to the output.
This commit is contained in:
committed by
Anselm R Garbe
parent
9a3b12525b
commit
3276fbea1c
55
libutil/cp.c
55
libutil/cp.c
@@ -12,7 +12,6 @@
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#include <utime.h>
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#include "../fs.h"
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#include "../text.h"
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#include "../util.h"
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int cp_aflag = 0;
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@@ -27,7 +26,7 @@ int
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cp(const char *s1, const char *s2, int depth)
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{
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DIR *dp;
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FILE *f1, *f2;
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int f1, f2;
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struct dirent *d;
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struct stat st;
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struct timespec times[2];
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@@ -113,46 +112,38 @@ cp(const char *s1, const char *s2, int depth)
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return 0;
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}
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} else {
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if (!(f1 = fopen(s1, "r"))) {
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weprintf("fopen %s:", s1);
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if ((f1 = open(s1, O_RDONLY)) < 0) {
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weprintf("open %s:", s1);
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cp_status = 1;
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return 0;
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}
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if (!(f2 = fopen(s2, "w"))) {
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if (cp_fflag) {
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if (unlink(s2) < 0 && errno != ENOENT) {
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weprintf("unlink %s:", s2);
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cp_status = 1;
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fclose(f1);
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return 0;
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} else if (!(f2 = fopen(s2, "w"))) {
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weprintf("fopen %s:", s2);
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cp_status = 1;
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fclose(f1);
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return 0;
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}
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} else {
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weprintf("fopen %s:", s2);
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if ((f2 = creat(s2, st.st_mode)) < 0 && cp_fflag) {
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if (unlink(s2) < 0 && errno != ENOENT) {
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weprintf("unlink %s:", s2);
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cp_status = 1;
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fclose(f1);
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close(f1);
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return 0;
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}
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f2 = creat(s2, st.st_mode);
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}
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if (f2 < 0) {
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weprintf("creat %s:", s2);
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cp_status = 1;
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close(f1);
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return 0;
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}
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if (concat(f1, s1, f2, s2) < 0) {
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cp_status = 1;
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close(f1);
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close(f2);
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return 0;
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}
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concat(f1, s1, f2, s2);
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/* preserve permissions by default */
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fchmod(fileno(f2), st.st_mode);
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fchmod(f2, st.st_mode);
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if (fclose(f2) == EOF) {
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weprintf("fclose %s:", s2);
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cp_status = 1;
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return 0;
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}
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if (fclose(f1) == EOF) {
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weprintf("fclose %s:", s1);
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cp_status = 1;
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return 0;
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}
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close(f1);
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close(f2);
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}
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if (cp_aflag || cp_pflag) {
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