This program reads a command (or any character sequence) from stdin and
takes the path to the history file as an argument. The history file should
be empty or contain a list of commands each of which should be followed
by a tab character and a usage count. An example for a line in such a
history file is the following.
st 234
updhist reads a command from stdin, increases its count in the history
file, writes the file out again (overwriting the old one) and then writes
the command to stdout before exiting.
---
updhist.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 84 insertions(+)
create mode 100644 updhist.c
diff --git a/updhist.c b/updhist.c
new file mode 100644
index 0000000..8078b3e
--- /dev/null
+++ b/updhist.c
@@ -0,0 +1,84 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "util.h"
+
+static void
+usage(void)
+{
+ printf("usage: updhist historyfile\n");
+ exit(0);
+}
+
+static void
+update_hist_file(char* p, char* cmdname, size_t len)
+{
+ FILE *hist = NULL, *nhist = NULL;
+ char *tmpname;
+ char buf[BUFSIZ];
+ int ret, searching = 1;
+ long int count;
+ size_t fnlen;
+
+ if (!(hist = fopen(p, "r")))
+ die("Could not open history file: %s\n", p);
+
+ fnlen = strlen(p);
+ tmpname = malloc(fnlen+5);
+ strcpy(tmpname, p);
+ strcat(tmpname, ".tmp");
+ if (!(nhist = fopen(tmpname, "w")))
+ die("Could not open the history file to write: %s\n", p);
+
+ while (fscanf(hist, "%200s\t%ld", buf, &count) == 2) {
+ if (searching) {
+ searching = strcmp(buf, cmdname);
+ if (searching==0)
+ count++;
+ }
+
+ fprintf(nhist, "%s\t%lu\n", buf, count);
+ }
+ if (searching)
+ fprintf(nhist, "%s\t%d\n", cmdname, 1);
+
+ ret = feof(hist);
+ if (!ret)
+ die("Could not parse history file completely. Exiting.\n");
+
+ fclose(hist);
+ fclose(nhist);
+
+ ret = rename(tmpname, p);
+ if (ret)
+ die("Could not overwrite old history file with the new one.
Exiting.\n");
+ free(tmpname);
+}
+
+int
+main(int argc, char *argv[])
+{
+ size_t n, len;
+ char stdinbuf[BUFSIZ];
+
+ if (argc < 2)
+ usage();
+
+ while ((n = fread(stdinbuf, 1, sizeof(stdinbuf), stdin))) {
+ if (fwrite(stdinbuf, 1, n, stdout) == n)
+ continue;
+ fprintf(stderr, "fwrite to stdout did not write all data. Wrote
only %lu bytes.\n", n);
+ }
+ fclose(stdout);
+
+ len = strlen(stdinbuf);
+ if (len == 0)
+ return 1;
+
+ stdinbuf[--len] = '\0';
+ update_hist_file(argv[1], stdinbuf, len);
+
+ return 0;
+}
--
2.6.2
