csv

commit 4a01eb737eae0d6d454a5cc7090336643886fe25
parent 31c1745c34d6adeb93fcd40d55aa43cedc80b6ec
Author: aabacchus <ben@bvnf.space>
Date:   Sat,  2 Oct 2021 21:25:03 +0100

start manpage, make own library source file

Diffstat:
A
csv.3
 | 
50
++++++++++++++++++++++++++++++++++++++++++++++++++
M
csv.c
 | 
3
++-
A
main.c
 | 
47
+++++++++++++++++++++++++++++++++++++++++++++++

3 files changed, 99 insertions(+), 1 deletion(-)
diff --git a/csv.3 b/csv.3
@@ -0,0 +1,50 @@
+.\" To view this file, run: man ./csv.3
+.Dd October 2, 2021
+.Dt CSV 3
+.Os "ben's space"
+.Sh NAME
+.Nm csv_read_file ,
+.Nm csv_create ,
+.Nm csv_destroy
+.Nd parse csv data
+.Sh LIBRARY
+.Lb csv
+.Sh SYNOPSIS
+.In csv.h
+.Bd -literal
+struct csv {
+    int cols, rows;
+    char **headers;    /* array of strings */
+    float **data;      /* array of arrays of floats */
+};
+
+.Ed
+.Ft int
+.Fn csv_read_file "FILE *stream" "struct csv *c" "char hdr"
+.Ft struct csv *
+.Fn csv_create
+.Ft void
+.Fn csv_destroy "struct csv *c"
+.Sh DESCRIPTION
+These functions reads csv data from
+.Va stream
+into memory, parsing each cell as a
+.Va float .
+.Pp
+If
+.Va hdr
+is set,
+.Nm
+parses the first line of
+.Va stream
+for column header names which are placed into
+.Va c->headers .
+.El
+.Pp
+The number of columns in the first row is set as the intended number
+of cells for every row. Extra cells on subsequent rows will be ignored.
+Any cells which are empty or missing will be set to
+.Va 0 ,
+and a warning will be printed.
+.Sh AUTHORS
+.An phoebos Aq Mt ben@bvnf.space
diff --git a/csv.c b/csv.c
@@ -2,7 +2,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 #include "csv.h"
 
 #define MAX_LINE 2048
@@ -149,6 +148,7 @@ cleanup:
 	return -1;
 }
 
+/*
 int
 main(int argc, char **argv) {
 	int c;
@@ -193,6 +193,7 @@ usage:
 	}
 	return 0;
 }
+*/
 
 int
 csv_read_file(FILE *f, struct csv *c, char hdr) {
diff --git a/main.c b/main.c
@@ -0,0 +1,47 @@
+#include <stdio.h>
+#include <unistd.h>
+#include "csv.h"
+
+int
+main(int argc, char **argv) {
+    int c;
+    char flag_H = 0;
+    while ((c = getopt(argc, argv, "Hh")) != -1) {
+        switch (c) {
+            case 'H':
+                flag_H = 1;
+                break;
+            case 'h':
+                goto usage;
+        }
+    }
+    if (argc - optind > 1) {
+usage:
+        fprintf(stderr,
+            "usage: %s [-H] [file]\n  if no filename given, data is read from stdin\n"
+            "  -H\tread data headers from first line\n", argv[0]);
+        return 1;
+    }
+
+    FILE *f;
+    if (argc - optind == 0) {
+        f = stdin;
+    } else {
+        f = fopen(argv[optind], "r");
+        if (f == NULL) {
+            perror(argv[optind]);
+            return 1;
+        }
+    }
+    struct csv *csv = csv_create();
+    if (csv == NULL) {
+        perror("csv_create");
+        return 1;
+    }
+    int ret = csv_read_file(f, csv, flag_H);
+    if (ret != 0) {
+        csv_destroy(csv);
+        return 1;
+    }
+    return 0;
+}